Receiving apparatus and data obtaining method

ABSTRACT

A receiving apparatus for communication area evaluation includes a receiving unit configured to receive a first signal transmitted from a base station; a delay profile calculation unit configured to calculate a downlink delay profile based on the first signal; and an estimated value calculation unit configured to calculate an estimated cyclic prefix length based on the calculated downlink delay profile.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of and, thereby,claims benefit under 35 U.S.C. §120 to U.S. patent application Ser. No.12/672,439 filed on Feb. 5, 2010, titled, “RECEIVING APPARATUS AND DATAOBTAINING METHOD,” which is a national stage application of PCTApplication No. PCT/JP2008/064112, filed on Aug. 6, 2008, which claimspriority to Japanese Patent Application No. 2007-211590 filed on Aug.14, 2007. The content of the priority application is incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention generally relates to a receiving apparatus. Moreparticularly, the present invention relates to a receiving apparatus anda data obtaining method for obtaining information regarding a mobilecommunication system.

BACKGROUND ART

In a mobile communication system, communication quality in radiocommunications greatly influences transmission characteristics andquality of service. To improve the transmission characteristics and tomaintain sufficient quality of service, network operators evaluatecommunication quality in their communication areas and try to improvethe communication quality by adjusting various parameters. Here,“communication quality” is represented, for example, by a delay profileor a received signal-to-interference ratio (SIR).

For a CDMA-based mobile communication system, Japanese PatentApplication Publication No. 11-193699, for example, discloses a servicearea evaluation system and a method and an apparatus for obtainingservice area evaluation data used for evaluation of communicationquality in a communication area. In CDMA, generally, dedicated channelsare used for communications and transmission power control is used forlink adaptation, a technology for adapting to fluctuations in receptionlevels such as Rayleigh fading and shadow fading.

Meanwhile, a successor communication system to W-CDMA, i.e., Long TermEvolution (LTE), is currently being discussed by 3GPP, a standardizationgroup for W-CDMA. In LTE, orthogonal frequency division multiplexing(OFDM) is to be used as a downlink radio access method andsingle-carrier frequency division multiple access (SC-FDMA) is to beused as an uplink radio access method (see, for example, 3GPP TR 25.814(V7.0.0), “Physical Layer Aspects for Evolved UTRA,” June 2006).

OFDM is a multi-carrier transmission method where a frequency band isdivided into multiple narrow frequency bands (subcarriers) and data aretransmitted on the subcarriers. The subcarriers are densely arrangedalong the frequency axis such that they partly overlap each other but donot interfere with each other. This method enables high-speedtransmission and improves frequency efficiency.

SC-FDMA is a single-carrier transmission method where a frequency bandis divided into multiple frequency bands and the frequency bands areallocated to different terminals for transmission in order to reduceinterference between the terminals. Also, SC-FDMA reduces variation ofthe transmission power and therefore makes it possible to reduce powerconsumption of terminals and to achieve wide coverage.

In a mobile communication system based on LTE, shared channels are usedfor both uplink and downlink, and adaptive modulation and coding (AMC)is used for link adaptation.

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

As described above, a mobile communication system based on LTE uses OFDMand SC-FDMA that are different from communication methods used in aCDMA-based mobile communication system. Also, while a CDMA-based mobilecommunication system uses transmission power control for link adaptationand dedicated channels for communications, a mobile communication systembased on LTE uses adaptive modulation and coding for link adaptation andshared channels for communications. Therefore, for a mobilecommunication system based on LTE, it is not possible to use, withoutchange, a receiving method and a receiving apparatus for service(communication) area evaluation as disclosed in Japanese PatentApplication Publication No. 11-193699

One object of the present invention is to provide a receiving apparatusand a data obtaining method that make it possible to evaluatecommunication quality in a communication area of a mobile communicationsystem employing OFDM and SC-FDMA, adaptive modulation and coding,and/or shared channels.

Means for Solving the Problems

According to an aspect of the present invention, a receiving apparatusincludes a receiving unit configured to receive a first signaltransmitted from a base station; a delay profile calculation unitconfigured to calculate a downlink delay profile based on the firstsignal; an estimated value calculation unit configured to calculate anestimated propagation path delay or an estimated cyclic prefix lengthbased on the calculated downlink delay profile; and an outputting unitconfigured to output the estimated propagation path delay or theestimated cyclic prefix length.

According to another aspect of the present invention, a receivingapparatus includes a receiving unit configured to receive a first signaltransmitted from a base station; an estimated value calculation unitconfigured to obtain downlink quality information based on the firstsignal and to calculate an estimated downlink throughput based on thedownlink quality information; and an outputting unit configured tooutput the estimated downlink throughput.

According to another aspect of the present invention, a receivingapparatus includes a receiving unit configured to receive a first signaltransmitted from multiple base stations that perform downlinktransmission in synchronization with each other; an estimated valuecalculation unit configured to obtain downlink quality information basedon the first signal and to calculate an estimated downlink throughputbased on the downlink quality information; and an outputting unitconfigured to output the estimated downlink throughput.

According to another aspect of the present invention, a receivingapparatus includes a communication unit configured to communicate with abase station; a receiving unit configured to receive a second signaltransmitted from the base station; an estimated value calculation unitconfigured to calculate an estimated downlink throughput based oninformation in the second signal; and an outputting unit configured tooutput the estimated downlink throughput.

According to another aspect of the present invention, a receivingapparatus includes a receiving unit configured to receive a first signaltransmitted from a base station; a first calculation unit configured tocalculate, based on the first signal, a received power level of thefirst signal, a downlink received power level, a value obtained bydividing the received power level of the first signal by the downlinkreceived power level, and a path loss for an entire frequency band of amobile communication system; a second calculation unit configured tocalculate, based on the first signal, the received power level of thefirst signal, the downlink received power level, the value obtained bydividing the received power level of the first signal by the downlinkreceived power level, and the path loss for a part of the entirefrequency band of the mobile communication system; and an outputtingunit configured to output the received power level of the first signal,the downlink received power level, the value obtained by dividing thereceived power level of the first signal by the downlink received powerlevel, and the path loss.

According to another aspect of the present invention, a receivingapparatus includes a receiving unit configured to receive a first signaltransmitted from a base station; a path loss calculation unit configuredto calculate a path loss based on the first signal; an uplink qualitycalculation unit configured to calculate, based on the path loss, anestimated uplink transmission power level of a fourth signal, anestimated uplink SIR, an estimated uplink throughput, and UE powerheadroom; and an outputting unit configured to output the estimateduplink transmission power level of the fourth signal, the estimateduplink SIR, the estimated uplink throughput, and the UE power headroom.

According to another aspect of the present invention, a receivingapparatus includes a communication unit configured to communicate with abase station; a receiving unit configured to receive a third signaltransmitted from the base station; an uplink quality calculation unitconfigured to calculate an estimated uplink transmission power level ofa fourth signal, an estimated uplink throughput, and UE power headroom;and an outputting unit configured to output the estimated uplinktransmission power level of the fourth signal, the estimated uplinkthroughput, and the UE power headroom.

According to another aspect of the present invention, a receivingapparatus includes a receiving unit configured to receive a fifth signaltransmitted from a base station; an error rate calculation unitconfigured to calculate an error rate of the fifth signal; and anoutputting unit configured to output the error rate of the fifth signal.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a first signal transmittedfrom a base station; a delay profile calculation step of calculating adownlink delay profile based on the first signal; an estimated valuecalculation step of calculating an estimated propagation path delay oran estimated cyclic prefix length based on the calculated downlink delayprofile; and an outputting step of outputting the estimated propagationpath delay or the estimated cyclic prefix length.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a first signal transmittedfrom a base station; a quality information obtaining step of obtainingdownlink quality information based on the first signal; an estimatedvalue calculation step of calculating an estimated downlink throughputbased on the downlink quality information; and an outputting step ofoutputting the estimated downlink throughput.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a first signal transmittedfrom multiple base stations that perform downlink transmission insynchronization with each other; a quality information obtaining step ofobtaining downlink quality information based on the first signal; anestimated value calculation step of calculating an estimated downlinkthroughput based on the downlink quality information; and an outputtingstep of outputting the estimated downlink throughput.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a second signaltransmitted from a base station; an estimated value calculation step ofcalculating an estimated downlink throughput based on information in thesecond signal; and an outputting step of outputting the estimateddownlink throughput.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a first signal transmittedfrom a base station; a first calculation step of calculating, based onthe first signal, a received power level of the first signal, a downlinkreceived power level, a value obtained by dividing the received powerlevel of the first signal by the downlink received power level, and apath loss for an entire frequency band of a mobile communication system;a second calculation step of calculating, based on the first signal, thereceived power level of the first signal, the downlink received powerlevel, the value obtained by dividing the received power level of thefirst signal by the downlink received power level, and the path loss fora part of the entire frequency band of the mobile communication system;and an output step of outputting the received power level of the firstsignal, the downlink received power level, the value obtained bydividing the received power level of the first signal by the downlinkreceived power level, and the path loss.

According to another aspect of the present invention, a data obtainingmethod includes a receiving step of receiving a first signal transmittedfrom a base station; a path loss calculation step of calculating a pathloss based on the first signal; an uplink quality calculation step ofcalculating, based on the path loss, an estimated uplink transmissionpower level of a fourth signal, an estimated uplink SIR, an estimateduplink throughput, and UE power headroom; and an outputting step ofoutputting the estimated uplink transmission power level of the fourthsignal, the estimated uplink SIR, the estimated uplink throughput, andthe UE power headroom.

According to still another aspect of the present invention, a dataobtaining method includes a receiving step of receiving a third signaltransmitted from a base station; an uplink quality calculation step ofcalculating an estimated uplink transmission power level of a fourthsignal, an estimated uplink throughput, and UE power headroom; and anoutputting step of outputting the estimated uplink transmission powerlevel of the fourth signal, the estimated uplink throughput, and the UEpower headroom.

Advantageous Effect of the Invention

An aspect of the present invention provides a receiving apparatus and adata obtaining method that make it possible to evaluate communicationquality in a communication area of a mobile communication systememploying OFDM and SC-FDMA, adaptive modulation and coding, and/orshared channels.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing illustrating a configuration of a radiocommunication system according to an embodiment of the presentinvention;

FIG. 2 is a drawing illustrating exemplary mapping of a downlinkreference signal to physical resources;

FIG. 3 is a block diagram of a base station according to an embodimentof the present invention;

FIG. 4 is a block diagram of a baseband signal processing unit of a basestation according to an embodiment of the present invention;

FIG. 5 is a block diagram of a receiving apparatus according to anembodiment of the present invention;

FIG. 6 is a block diagram illustrating a receiving unit of a basebandsignal processing unit of a receiving apparatus according to anembodiment of the present invention;

FIG. 7 is a drawing used to describe an exemplary method of calculatingCQIs;

FIG. 8 is a drawing used to describe an exemplary method of calculatingCQIs;

FIG. 9 is a block diagram illustrating a receiving unit of a basebandsignal processing unit of a receiving apparatus according to anembodiment of the present invention;

FIG. 10 is a graph used to describe an average delay profile calculationprocess at a baseband signal processing unit of a receiving apparatusaccording to an embodiment of the present invention;

FIG. 11 is a graph used to describe an average delay profile calculationprocess at a baseband signal processing unit of a receiving apparatusaccording to an embodiment of the present invention;

FIG. 12 is a flowchart showing a data obtaining process performed by areceiving apparatus according to an embodiment of the present invention;

FIG. 13 is a flowchart showing a data obtaining process performed by areceiving apparatus according to an embodiment of the present invention;

FIG. 14 is a flowchart showing a data obtaining process performed by areceiving apparatus according to an embodiment of the present invention;

FIG. 15 is a flowchart showing a data obtaining process performed by areceiving apparatus according to an embodiment of the present invention;

FIG. 16 is a drawing illustrating a configuration of a radiocommunication system according to an embodiment of the presentinvention;

FIG. 17 is a block diagram illustrating a receiving unit of a basebandsignal processing unit of a receiving apparatus according to anembodiment of the present invention;

FIG. 18 is a block diagram of a receiving apparatus according to anembodiment of the present invention; and

FIG. 19 is a block diagram illustrating a receiving unit of a basebandsignal processing unit of a receiving apparatus according to anembodiment of the present invention.

EXPLANATION OF REFERENCES

-   -   50 _(l) (50 ₁, 50 ₂, 50 ₃, . . . , 50 _(l)) Cell    -   100 _(n) (100 ₁, 100 ₂, 100 ₃, . . . , 100 _(n)) User device    -   200 _(m) (200 ₁, 200 ₂, 200 ₃, . . . , 200 _(m)) Base station    -   202 Transceiver antenna    -   204 Amplifier    -   206 Transceiver unit    -   208 Baseband signal processing unit    -   2081 Layer 1 processing unit    -   20811 Transmission processing unit    -   20812 Reception processing unit    -   20813 Control channel signal generating unit    -   20814 Data channel signal generating unit    -   20815 Broadcast channel signal generating unit    -   20816 Reference signal generating unit    -   20817 Uplink demodulation unit    -   2082 MAC processing unit    -   2083 RLC processing unit    -   2084 Out-of-sync determining unit    -   210 Call processing unit    -   212 Transmission path interface    -   300 Access gateway    -   400 Core network    -   500 Physical uplink shared channel    -   600 Receiving apparatus    -   602 Antenna    -   604 Amplifier    -   606 Transceiver unit    -   608 Baseband signal processing unit    -   6080 Analog-to-digital conversion unit (A/D)    -   6081 CP removing unit    -   6082 Fast Fourier transform unit (FFT)    -   6083 Demultiplexing unit (DeMUX)    -   6084 Data signal decoding unit    -   6085 Downlink reference signal receiving unit    -   6086 Uplink quality measuring unit    -   6087 Downlink quality measuring unit    -   6088 Delay profile measuring unit    -   6089 Reference signal measuring unit    -   6090 Error rate obtaining unit    -   6091 MAC processing unit    -   6092 RLC processing unit    -   6093 Signal generating unit    -   6094 Transmission processing unit    -   610 External input/output unit    -   612 Call processing unit    -   614 Application unit    -   700 Global positioning system (GPS)

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

The best mode for carrying out the invention is described based on thefollowing embodiments with reference to the accompanying drawings.Throughout the accompanying drawings, the same reference numbers areused for parts having the same functions, and overlapping descriptionsof those parts are omitted.

A receiving apparatus 600 of this embodiment is used to evaluatecommunication quality in a communication area. The receiving apparatus600 receives a downlink signal transmitted from a base station,calculates downlink communication quality and uplink communicationquality based on the received signal, and outputs the calculatedquality. Accordingly, in this embodiment, a receiving unit for receivinga reference signal, a calculation unit for calculating downlink anduplink communication quality, and an output unit for outputting thecalculated communication quality included in the receiving apparatus 600are mainly described.

A radio communication system 1000 including the receiving apparatus 600and a base station 200 of this embodiment is described below withreference to FIG. 1.

The radio communication system 1000 is based on, for example, EvolvedUTRA and UTRAN (also called Long Term Evolution (LTE) or Super 3G). Theradio communication system 1000 includes the base station (eNode B: eNB)200, mobile stations 100 _(n) (100 ₁, 100 ₂, 100 ₃ . . . 100 _(n), wheren is an integer greater than 0), and the receiving apparatus 600 locatedin a cell 50 that is an area where a mobile communication service isprovided by the base station 200. The base station 200 is connected toan upper node such as an access gateway 300 and the access gateway 300is connected to a core network 400. The access gateway 300 may also becalled a mobility management entity/serving gateway (MME/SGW).

In FIG. 1, for brevity, only one sector is shown for the base station200. However, the base station 200 may have two or more sectors.

The receiving apparatus 600 may or may not be communicating with thebase station 200 based on Evolved UTRA and UTRAN. When the receivingapparatus 600 communicates with the base station 200 based on EvolvedUTRA and UTRAN, communication processing similar to that performedbetween the mobile stations 100 _(n) and the base station 200 isperformed between the receiving apparatus 600 and the base station 200.

The mobile stations 100 _(n) (100 ₁, 100 ₂, 100 ₃, . . . , 100 _(n))have the same configuration and functions and are therefore called themobile station 100 _(n) or the mobile stations 100 _(n) in thedescriptions below unless otherwise mentioned. Although mobile stationsare used as examples of user equipment (UE) communicating with a basestation in the descriptions below, user equipment communicating with abase station may also include fixed terminals.

In the radio communication system 1000, orthogonal frequency divisionmultiplexing (OFDM) is used as the downlink radio access method andsingle-carrier frequency division multiple access (SC-FDMA) is used asthe uplink radio access method. In OFDM, as described above, a frequencyband is divided into narrow frequency bands (subcarriers) and data aretransmitted on the subcarriers. In SC-FDMA, a frequency band is dividedinto multiple frequency bands and the frequency bands are allocated todifferent terminals for transmission in order to reduce interferencebetween the terminals.

Communication channels used in Evolved UTRA and UTRAN are describedbelow.

For downlink, a physical downlink shared channel (PDSCH) shared by themobile stations 100 _(n) and a physical downlink control channel(PDCCH), which is a downlink control channel for LTE, are used. Indownlink, the physical downlink control channel is used to report:downlink scheduling information including information on users to bemapped to the physical downlink shared channel and transport formatinformation for the physical downlink shared channel; an uplinkscheduling grant including information on users to be mapped to aphysical uplink shared channel and transport format information for thephysical uplink shared channel; and acknowledgement information for anuplink shared channel. Meanwhile, the physical downlink shared channelis used to transmit packet data. A transport channel for the packet datais a downlink shared channel (DL SCH). The downlink schedulinginformation may also be called downlink assignment information or adownlink scheduling grant. The downlink scheduling information and theuplink scheduling grant may be collectively called downlink controlinformation.

Also in downlink, a downlink reference signal is transmitted as a pilotsignal. The downlink reference signal is a two-dimensional sequencecomposed of a two-dimensional orthogonal sequence and a two-dimensionalpseudo random sequence (see, for example, 3GPP TS 36.211 (V1.0.0),“Physical Channels and Modulation,” March 2007). Instead, the downlinkreference signal may be composed of a two-dimensional pseudo randomsequence only. FIG. 2 shows exemplary mapping of the downlink referencesignal to physical resources.

For uplink, a physical uplink shared channel (PUSCH) shared by themobile stations 100 _(n) and an LTE uplink control channel are used.There are two types of uplink control channels: the first is an uplinkcontrol channel to be time-division-multiplexed with the physical uplinkshared channel, and the second is an uplink control channel to befrequency-division-multiplexed with the physical uplink shared channel.The uplink control channel to be frequency-division-multiplexed with thephysical uplink shared channel is called a physical uplink controlchannel (PUCCH). A control signal mapped to the uplink control channelto be time-division-multiplexed with the physical uplink shared channelmay be transmitted as a part of the physical uplink shared channel. Inuplink, the LTE physical uplink control channel is used to reportdownlink quality information (channel quality indicator: CQI) used forscheduling and adaptive modulation and coding (AMC) of a downlink sharedchannel and to transmit acknowledgement information (HARQ ACKinformation) for a downlink shared channel. Meanwhile, the physicaluplink shared channel is used to transmit packet data. A transportchannel for the packet data is an uplink shared channel (UL-SCH).

Examples of the packet data include IP packets in Web browsing, FTP, andVoIP, and a control signal for radio resource control (RRC). Hereafter;packet data may also be called user data. Corresponding transportchannels for the packet data (user data) are the DL-SCH and the UL-SCH,and corresponding logical channels for the packet data (user data) are adedicated traffic channel (DTCH) and a dedicated control channel (DCCH).

The base station 200 of this embodiment is described below withreference to FIG. 3.

The base station 200 of this embodiment includes a transceiver antenna202, an amplifier 204, a transceiver unit 206, a baseband signalprocessing unit 208, a call processing unit 210, and a transmission pathinterface 212.

Downlink packet data (user data) to be transmitted from the base station200 to the mobile station 100 _(n) are sent from an upper node such asthe access gateway 300 to the base station 200 and input to the basebandsignal processing unit 208 via the transmission path interface 212.

The baseband signal processing unit 208 performs, for the downlinkpacket data, PDCP layer transmission processing;segmentation/concatenation; RLC layer transmission processing such astransmission processing in RLC (radio link control) retransmissioncontrol; MAC (medium access control) retransmission control such astransmission processing in hybrid automatic repeat request (HARQ);scheduling; selection of transport formats; channel coding; and IFFT(inverse fast Fourier transform) processing. Then, the baseband signalprocessing unit 208 inputs the processed packet data to the transceiverunit 206. The baseband signal processing unit 208 also performstransmission processing such as channel coding and IFFT processing on aphysical downlink control channel signal (downlink control channel forLTE) and a broadcast channel signal, and inputs the processed signals tothe transceiver unit 206. Further, the baseband signal processing unit208 generates a downlink reference signal (downlink pilot signal). Thebaseband signal processing unit 208 multiplexes the downlink referencesignal, the packet data, the physical downlink control channel signal,and the broadcast channel signal, and inputs the multiplexed signal(baseband signal) to the transceiver unit 206.

The transceiver unit 206 performs frequency conversion to convert thebaseband signal output from the baseband signal processing unit 208 intoa radio frequency signal. The radio frequency signal is amplified by theamplifier 204 and transmitted from the transceiver antenna 202.

Meanwhile, when a radio frequency signal including uplink packet data istransmitted from the mobile station 100 _(n) to the base station 200,the radio frequency signal is received by the transceiver antenna 202,amplified by the amplifier 204, and frequency-converted by thetransceiver unit 206 into a baseband signal. Then, the transceiver unit206 inputs the baseband signal to the baseband signal processing unit208.

For the packet data in the input baseband signal, the baseband signalprocessing unit 208 performs FFT processing, IDFT processing, errorcorrection decoding, reception processing in MAC retransmission control,RLC layer reception processing, PDCP layer reception processing, and soon. The processed packet data are transferred via the transmission pathinterface 212 to the access gateway 300. The baseband signal processingunit 208 also performs FFT processing and error correction decoding onacknowledgement information for a downlink shared channel and downlinkquality information transmitted from the mobile station 100 _(n) andincluded in the baseband signal.

The call processing unit 210 performs call processing such asestablishment and release of communication channels, status managementof the base station 200, and management of radio resources.

Next, a configuration of the baseband signal processing unit 208 isdescribed with reference to FIG. 4.

The baseband signal processing unit 208 includes a layer 1 processingunit 2081, a MAC (medium access control) processing unit 2082, and anRLC processing unit 2083. The layer 1 processing unit 2081 includes atransmission processing unit 20811, a reception processing unit 20812, acontrol channel signal generating unit 20813, a data channel signalgenerating unit 20814, a broadcast channel signal generating unit 20815,a reference signal generating unit 20816, and an uplink demodulationunit 20817.

The layer 1 processing unit 2081, the MAC processing unit 2082, and theRLC processing unit 2083 of the baseband signal processing unit 208 andthe call processing unit 210 are connected to each other. The controlchannel signal generating unit 20813, the data channel signal generatingunit 20814, the broadcast channel signal generating unit 20815, and theuplink demodulation unit 20817 of the layer 1 processing unit 2081 andthe MAC processing unit 2082 are connected to each other.

The layer 1 processing unit 2081 performs channel coding and IFFTprocessing on downlink transmission signals, and performs channeldecoding and FFT processing on uplink transmission signals.

The control channel signal generating unit 20813 performs encoding, suchas turbo coding and/or convolutional coding, and interleaving on aphysical downlink control channel (PDCCH) to generate a PDCCH signal,and inputs the PDCCH signal to the transmission processing unit 20811.The data channel signal generating unit 20814 performs encoding, such asturbo coding and/or convolutional coding, and interleaving on a downlinkshared channel (DL-SCH) (corresponding to a physical downlink sharedchannel (PDSCH)) to generate a DL-SCH signal, and inputs the DL-SCHsignal to the transmission processing unit 20811. The broadcast channelsignal generating unit 20815 performs encoding, such as turbo codingand/or convolutional coding, and interleaving on a broadcast channel(BCH) (corresponding to a physical broadcast channel (P-BCH) or adynamic broadcast channel (D-BCH)) to generate a BCH signal, and inputsthe BCH signal to the transmission processing unit 20811. The dynamicbroadcast channel is also called a broadcast channel transmitted via thephysical downlink shared channel (BCH on PDSCH). The reference signalgenerating unit 20816 generates a downlink reference signal and inputsthe downlink reference signal to the transmission processing unit 20811.The transmission processing unit 20811 multiplexes the input signals,performs IFFT processing on the multiplexed signal, adds CPs to theIFFT-processed signal, and inputs the resulting signal to thetransceiver unit 206.

Meanwhile, when an uplink signal including, for example, an uplinkshared channel, downlink quality information, and acknowledgementinformation for a downlink shared channel is received from the mobilestation 100 _(n), the transceiver unit 206 converts the signal into abaseband signal and inputs the baseband signal to the receptionprocessing unit 20812. The reception processing unit 20812 performs CPremoval, FFT processing, frequency equalization, and inverse discreteFourier transform (IDFT) processing on the baseband signal, and inputsthe processed signal to the uplink demodulation unit 20817. The uplinkdemodulation unit 20817 decodes the (convolutional-coded and/orturbo-coded) signal, and inputs the decoded signal to the MAC processingunit 2082.

The MAC processing unit 2082 receives, from the uplink demodulation unit20817 of the layer 1 processing unit 2081, the decoded signal includingthe downlink quality information, the acknowledgement information for adownlink shared channel, and the uplink shared channel.

The MAC processing unit 2082 performs MAC retransmission control such astransmission processing in HARQ, scheduling, selection of transportformats, allocation of frequency resources, and so on for downlinkpacket data. Here, “scheduling” indicates a process of selecting mobilestations allowed to receive the downlink packet data using a downlinkshared channel in a given subframe. “Selection of transport formats”indicates a process of determining modulation schemes, coding rates, anddata sizes of the downlink packet data to be received by the mobilestations selected in the scheduling. The modulation schemes, codingrates, and data sizes are determined, for example, based on CQIsreported via uplink by the mobile stations. “Allocation of frequencyresources” indicates a process of allocating resource blocks to thedownlink packet data to be received by the mobile stations selected inthe scheduling. The resource blocks are allocated, for example, based onCQIs reported via uplink by the mobile stations. The CQIs reported bythe mobile stations are input from the layer 1 processing unit 2081 tothe MAC processing unit 2082. The MAC processing unit 2082 generatesdownlink scheduling information including IDs of users (mobile stations)allowed to communicate using the physical downlink shared channel andtransport format information for downlink packet data to be transmittedvia the physical downlink shared channel. The downlink schedulinginformation is determined through the scheduling, the selection oftransport formats, and the allocation of frequency resources describedabove. The MAC processing unit 2082 inputs the downlink schedulinginformation to the layer 1 processing unit 2081. The MAC processing unit2082 also inputs the downlink packet data to be transmitted to themobile stations to the layer 1 processing unit 2081.

Also, the MAC processing unit 2082 performs reception processing in MACretransmission control, scheduling, selection of transport formats,allocation of frequency resources, and so on for uplink packet data.Here, “scheduling” indicates a process of selecting mobile stationsallowed to transmit the uplink packet data using an uplink sharedchannel in a given subframe. “Selection of transmission formats”indicates a process of determining modulation schemes, coding rates, anddata sizes of the uplink packet data to be transmitted by the mobilestations selected in the scheduling. The modulation schemes, codingrates, and data sizes are determined, for example, based on SIRs ofsounding reference signals (SRS) transmitted from the mobile stationsvia uplink and/or path losses between the base station and the mobilestations. “Allocation of frequency resources” indicates a process ofallocating resource blocks to the uplink packet data to be transmittedby the mobile stations selected in the scheduling. The resource blocksare allocated, for example, based on SIRs of sounding reference signals(SRS) transmitted from the mobile stations via uplink. The MACprocessing unit 2082 generates an uplink scheduling grant(s) includingIDs of users (mobile stations) allowed to communicate using the physicaluplink shared channel and transport format information for uplink packetdata to be transmitted via the physical uplink shared channel. Theuplink scheduling grant is determined through the scheduling, theselection of transport formats, and the allocation of frequencyresources described above. The MAC processing unit 2082 inputs theuplink scheduling grant to the layer 1 processing unit 2081. The MACprocessing unit 2082 also generates acknowledgement information for theuplink shared channel (UL-SCH) based on its demodulation result, andinputs the acknowledgement information to the layer 1 processing unit2081.

The RLC processing unit 2083 performs, for downlink packet data, RLClayer transmission processing such as segmentation/concatenation andtransmission processing in RLC retransmission control; and performs, foruplink packet data, RLC layer reception processing for uplink packetdata such as segmentation/concatenation and reception processing in RLCretransmission control. The RLC processing unit 2083 may be configuredto perform PDCP layer processing in addition to the RLC layer processingdescribed above.

Next, the receiving apparatus 600 of this embodiment is described withreference to FIG. 5. The receiving apparatus 600 receives a downlinksignal transmitted from the base station 200, calculates downlinkcommunication quality and uplink communication quality based on thereceived signal, and outputs the calculated quality. Components relevantto these functions of the receiving apparatus 600 are mainly describedbelow.

As shown in FIG. 5, the receiving apparatus 600 includes an antenna 602,an amplifier 604, a transceiver unit 606, a baseband signal processingunit 608, and an external input/output unit 610.

A downlink radio frequency signal transmitted from the base station 200is received by the antenna 602 and input to the amplifier 604. Theamplifier 604 amplifies the radio frequency signal and inputs theamplified radio frequency signal to the transceiver unit 606. Thetransceiver unit 606 frequency-converts the amplified radio frequencysignal into a baseband signal and inputs the baseband signal to thebaseband signal processing unit 608. Then, the baseband signalprocessing unit 608 performs reception processing for the basebandsignal such as FFT processing and error correction decoding.

Also, based on a downlink reference signal in the baseband signal, thebaseband signal processing unit 608 performs an expected (estimated) CPlength calculation process of calculating a delay profile and outputtingan estimated propagation path delay or an expected (estimated) cyclicprefix (CP) length; a downlink quality calculation process ofcalculating downlink quality and/or an expected (estimated) downlinkthroughput; an uplink quality calculation process of calculating anexpected (estimated) uplink transmission power level and/or an expected(estimated) uplink throughput; and a measuring process of calculating areception level of the reference signal and/or a downlink receptionlevel. In the descriptions below, the term “expected” may be replacedwith “estimated”.

Next, a configuration of the baseband signal processing unit 608 isdescribed with reference to FIG. 6. The baseband signal processing unit608 includes an analog-to-digital conversion unit (A/D) 6080, a CPremoving unit 6081, an FFT 6082, a DeMUX 6083, a data signal decodingunit 6084, a downlink reference signal receiving unit 6085, an uplinkquality measuring unit 6086, a downlink quality measuring unit 6087, adelay profile measuring unit 6088, a reference signal measuring unit6089, and an error rate obtaining unit 6090.

The analog-to-digital conversion unit (A/D) 6080 converts an analogbaseband signal input from the transceiver unit 606 into a digitalsignal and inputs the digital signal to the CP removing unit 6081.

The CP removing unit 6081 removes CPs from received symbols and inputsremaining effective symbols to the FFT 6082.

The fast Fourier transform unit (FFT) 6082 fast-Fourier-transforms theinput signal and thereby OFDM-demodulates the signal, and inputs thedemodulated signal to the DeMUX 6083.

The demultiplexing unit (DeMUX) 6083 separates a downlink referencesignal and a common channel signal from the demodulated signal, inputsthe downlink reference signal to the downlink reference signal receivingunit 6085, and inputs the common channel signal to the data signaldecoding unit 6084.

The downlink reference signal receiving unit 6085 performs channelestimation based on the downlink reference signal and determines channelcompensation to be applied to a received data signal. In other words,the downlink reference signal receiving unit 6085 calculates a channelestimate. The downlink reference signal receiving unit 6085 inputs thecalculated channel estimate to the data signal decoding unit 6084. Thedownlink reference signal receiving unit 6085 also inputs the downlinkreference signal and the channel estimate to the uplink qualitymeasuring unit 6086, the downlink quality measuring unit 6087, the delayprofile measuring unit 6088, the reference signal measuring unit 6089,and the error rate obtaining unit 6090.

The data signal decoding unit 6084 receives the channel estimate fromthe downlink reference signal receiving unit 6085, and applies channelcompensation based on the channel estimate to the downlink data signalreceived from the base station 200 to decode the downlink data signal.Here, the data signal indicates the common channel signal transmittedfrom the base station 200. The common channel signal, for example,includes common channels such as a physical broadcast channel (P-BCH), adynamic broadcast channel (D-BCH), downlink scheduling information forthe D-BCH, a paging channel (PCH), and/or a paging indicator (PI)(downlink scheduling information for the PCH). After decoding the datasignal, the data signal decoding unit 6084 reports the decoding resultsto the error rate obtaining unit 6090. Logical channels corresponding tothe common channels are, for example, a broadcast control channel (BCCH)and a paging control channel (PCCH).

Also, the data signal decoding unit 6084 obtains information from theP-BCH and the D-BCH, and inputs the obtained information to relevantcomponents of the receiving apparatus 600 as needed. For example, thedata signal decoding unit 6084 may obtain information regarding thetransmission power level of the downlink reference signal from the P-BCHor the D-BCH, and input the obtained information to the uplink qualitymeasuring unit 6086 and the reference signal measuring unit 6089. Also,the data signal decoding unit 6084 may obtain information (P0) regardinguplink transmission power control from the P-BCH or the D-BCH, and inputthe obtained information to the uplink quality measuring unit 6086.

The uplink quality measuring unit 6086 receives the channel estimate andthe downlink reference signal from the downlink reference signalreceiving unit 6085. Based on the downlink reference signal, the uplinkquality measuring unit 6086 calculates a path loss; and calculates anexpected (estimated) uplink transmission power level, an expected(estimated) uplink SIR, an expected (estimated) uplink throughput, andUE power headroom based on the calculated path loss.

A method of calculating the path loss is described below. First, areceived power level of the downlink reference signal (reference signalreceived power (RSRP)) is calculated based on the channel estimate andthe downlink reference signal (see, 3GPP TS36.214, v 1.0.0, 2007-05, fora definition of the reference signal received power (RSRP)). Then, apath loss is calculated based on the received power level of thedownlink reference signal and a transmission power level of the downlinkreference signal at the base station 200 as follows:Path loss=(transmission power level of downlink referencesignal)−(received power level of downlink reference signal)

In the above formula, the path loss is represented in dB.

The transmission power level of the downlink reference signal may beprovided as a parameter in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610. Also, thetransmission power level of the downlink reference signal may bedetermined based on the information regarding the transmission powerlevel of the downlink reference signal obtained from the P-BCH or theD-BCH. The information regarding the transmission power level of thedownlink reference signal obtained from the P-BCH or the D-BCH is inputfrom the data signal decoding unit 6084.

Meanwhile, if the receiving apparatus 600 includes two receivingantennas, the received power level of the downlink reference signal anda downlink received carrier power level may be measured in one of thefollowing three methods:

(1) Using a value measured at one of the two antennas (main antenna).

(2) Using an average of values measured at the two antennas.

(3) Using the sum of values measured at the two antennas.

The three methods may be provided as parameters in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610.

Based on the calculated path loss, the uplink quality measuring unit6086 calculates an expected (estimated) transmission power level of anuplink transmission signal, an expected (estimated) uplink throughput,and UE power headroom.

For example, the uplink quality measuring unit 6086 calculates anexpected transmission power level of a physical uplink shared channelusing the following formula:Expected transmission power level=min(Pmax,10*log M+P0+a1*PL+delta_(—)mcs+f(delta_(—) i))

where,

Pmax: the maximum transmission power level of mobile station (e.g., 24dBm)

M (M_(pusch)): the number of allocated resource blocks

P0 (P0_(pusch)): a value reported via a broadcast channel

a1 (α): a coefficient

PL: path loss

delta_mcs (Δ_(TF)(i)): a value reported via an RRC message * “i” inΔ_(TF)(i) indicates an index indicating a time unit such as a subframenumber.

delta_i: a correction parameter, may be simply called “i”

f(*): a function that takes delta_i as an argument

Pmax, M, P0, a1, delta_mcs, delta_i, and f(*) may be provided asparameters in the receiving apparatus 600 or may be input from theoutside via the external input/output unit 610. Also, P0 may bedetermined based on the information regarding uplink transmission powercontrol obtained from the P-BCH or the D-BCH. The information (P0)regarding uplink transmission power control is input from the datasignal decoding unit 6084.

The above formula for obtaining an expected transmission power level isjust an example. Any appropriate formula taking a path loss as anargument may be used to calculate an expected transmission power levelof the physical uplink shared channel.

In the above example, an expected transmission power level of thephysical uplink shared channel is obtained using a formula.Alternatively, an expected transmission power level of a soundingreference signal, an uplink control channel, or a random access channelmay be calculated using a similar formula. Also, an expectedtransmission power level of a sounding reference signal, an uplinkcontrol channel, or a random access channel may be calculated byoffsetting the expected transmission power level of the physical uplinkshared channel.

An expected. UE power headroom (UPH) may be calculated based on theexpected transmission power level of the physical uplink shared channelusing the following formula:Expected UPH [dB]=Pmax−(expected transmission power level of physicaluplink shared channel)

Similarly, expected UPHs regarding the sounding reference signal, theuplink control channel, and the random access channel may be calculatedbased on their expected transmission power levels as follows:Expected UPH(for SRS)=Pmax−(expected transmission power level ofsounding reference signal)Expected UPH(for uplink control channel)=Pmax(expected transmissionpower level of uplink control channel)Expected UPH(for RACH)=Pmax−(expected transmission power level of randomaccess channel)

The expected transmission power levels and the expected UPHs describedabove may be represented by averages in the frequency domain and/or thetime domain. An average in the time domain may be calculated over anaveraging period defined as a parameter. For example, an average may becalculated over an averaging period of 1 ms. Also, the averagecalculated over 1 ms may be filtered using the following formula toobtain a value F_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 1 ms

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

Instead of averaging calculated values in the time domain as describedabove, calculated values may be averaged based on positional informationof the receiving apparatus 600. For example, the expected transmissionpower levels and the expected UPHs described above may be averaged overan averaging interval of 100 m, i.e., every 100-m movement of thereceiving apparatus 600. A two-dimensional parameter such as 100 m² maybe specified for the averaging interval instead of a one-dimensionalparameter such as 100 m. The positional information is input via theexternal input/output unit 110. The averaging interval based on thepositional information may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610.

An average in the frequency domain may be calculated, as shown in FIG.7, over the entire system frequency band, or over a center frequencyband of 1.08 MHz located in the center of the system frequency band,i.e., including the center frequency of the system frequency band. InFIG. 7, the center frequency band is composed of six resource blocks andincludes the center frequency of the system frequency band. Thehorizontal axis in FIG. 7 indicates frequency. In LTE, the centerfrequency band of 1.08 MHz is used to transmit a synchronization channel(SCH) (or a synchronization signal). An average may instead becalculated over each resource block, or more flexibly, over anyfrequency band specified in the system frequency band. Further, as shownin FIG. 8, an average may be calculated over each resource block groupincluding multiple resource blocks. In the example of FIG. 8, oneresource block group includes five resource blocks. The horizontal axisin FIG. 8 indicates frequency. The averaging interval (or range) in thefrequency domain may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610.

If the expected uplink transmission power level or the expected UPH isto be calculated for each resource block or resource block group,expected uplink transmission power levels or expected UPHs may becalculated for M (where M>0) resource blocks or resource block groupsselected in ascending order of the path loss. The value M may beprovided as a parameter in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

An expected uplink throughput may be calculated as described below basedon the expected uplink transmission power level, the path loss, and aninterference level.

First, an expected uplink SIR at the base station 200 is calculated asfollows:Expected uplink SIR=(expected uplink transmission power level)−(pathloss)−(interference level)

The interference level may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610. In either case, the interference level is a valuethat is normalized with respect to a bandwidth of a frequency band forwhich the expected uplink transmission power level is calculated.

Next, an expected uplink throughput is calculated based on a look-uptable as exemplified by table 1 and the expected uplink SIR. Table 1shows the correspondence between expected SIRs [dB] and throughputs[Mbps] per resource block.

TABLE 1 Throughput per resource Expected SIR X [dB] block [Mbps] X <−3.5 dB 0.0 −3.5 dB ≦ X < −2.5 dB 0.1 −2.5 dB ≦ X < −1.5 dB 0.12 −1.5 dB≦ X < −0.5 dB 0.15 −0.5 dB ≦ X < 0.5 dB 0.2   0.5 dB ≦ X < 1.5 dB 0.25 .. . . . . 25.5 dB ≦ X 60

Table 1 is used to identify a throughput per resource block.Alternatively, a look-up table for identifying a throughput of theentire system frequency band or a throughput of a given frequency bandin the system frequency band may be used.

As described above, the expected uplink transmission power level may berepresented by an average in the time domain and/or the frequencydomain. Similarly, the expected uplink SIR and the expected uplinkthroughput may be represented by averages in the time domain and/or thefrequency domain.

For example, the expected uplink throughput may be obtained by averagingcalculated values in the time domain over the averaging period andfiltering the averaged value based on the filtering factor “a”.

Instead of averaging calculated values in the time domain as describedabove, calculated values may be averaged based on positional informationof the receiving apparatus 600. For example, the expected uplink SIR andthe expected uplink throughput may be obtained by averaging calculatedvalues over an averaging interval of 100 m, i.e., every 100-m movementof the receiving apparatus 600. A two-dimensional parameter such as 100m² may be specified for the averaging interval instead of aone-dimensional parameter such as 100 m. The positional information isinput via the external input/output unit 610. The averaging intervalbased on the positional information may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

An average in the frequency domain of the expected uplink throughput maybe calculated over the entire system frequency band, over a centerfrequency band of 1.08 MHz located in the center of the system frequencyband, i.e., including the center frequency of the system frequency band,over a given frequency band in the system frequency band, over eachresource block, or over each resource block group. If the expectedthroughput is to be calculated for each resource block or resource blockgroup, the highest M expected throughputs of resource blocks or resourceblock groups may be selected.

The averaging period in the time domain, the filtering factor “a”, theaveraging interval (or range) in the frequency domain, and the value Mmay be provided as parameters in the receiving apparatus 600 or may beinput from the outside via the external input/output unit 610.

The look-up table of table 1 is just an example, and any appropriatelook-up table containing different values may be used for thecalculations described above.

In addition to calculating the expected uplink transmission power level,the expected uplink SIR, the expected uplink throughput, and theexpected UPH based on the downlink reference signal transmitted from thebase station 200, those values may also be calculated based on adownlink reference signal transmitted from a neighboring base station.Also, if each base station covers multiple sectors, the above expectedvalues may be calculated based on downlink reference signals transmittedfrom all sectors of the base station 200 and the neighboring basestation. Further, the uplink quality measuring unit 6086 may beconfigured to calculate the expected uplink transmission power level,the expected uplink SIR, the expected uplink throughput, and theexpected UPH based on reference signals from all base stations (orsectors) that the receiving apparatus 600 can receive.

After calculations, the uplink quality measuring unit 6086 inputs theexpected uplink transmission power level, the expected uplink SIR, theexpected uplink throughput, and the expected UPH to the externalinput/output unit 610.

The expected uplink transmission power level, the expected uplink SIR,the expected uplink throughput, and the expected UPH input to theexternal input/output unit 610 are output, for example, as graphs ornumerical data to the outside (e.g., a monitor screen or a storagemedium) as described later. Also, the expected uplink transmission powerlevel, the expected uplink SIR, the expected uplink throughput, and theexpected UPH may be output, for example, as graphs or numerical data tothe outside (e.g., a monitor screen or a storage medium) together withthe positional information of the receiving apparatus 600. Thus, theexpected uplink transmission power level, the expected uplink SIR, theexpected uplink throughput, and the expected UPH are output to theoutside and thereby made available to a network operator (or a user, adevice, or so on). In short, the receiving apparatus 600 calculates theexpected uplink transmission power level, the expected uplink SIR, theexpected uplink throughput, and the expected UPH based on a downlinkreference signal transmitted from the base station 200, and therebymakes it possible to evaluate uplink transmission efficiency, radiocapacity, and cell coverage of the radio communication system 1000.

The downlink quality measuring unit 6087 receives the channel estimateand the downlink reference signal from the downlink reference signalreceiving unit 6085. Based on the channel estimate and the downlinkreference signal, the downlink quality measuring unit 6087 calculatesdownlink quality information (channel quality indicator) and an expecteddownlink throughput.

For example, the downlink quality information is obtained by referringto a look-up table as shown by table 2 based on an SIR of the downlinkreference signal. Table 2 shows the correspondence between CQIs and SIRs[dB]. Alternatively, the SIR itself may be used as the downlink qualityinformation.

TABLE 2 CQI SIR X [dB] 0 X < −3.5 dB 1 −3.5 dB ≦ X < −2.5 dB 2 −2.5 dB ≦X < −1.5 dB 3 −1.5 dB ≦ X < −0.5 dB . . . . . . 30  25.5 dB ≦ X

Also, the downlink quality information may be obtained by referring to alook-up table as shown by table 3. Table 3 shows the correspondencebetween CQIs, the numbers of resource blocks (No. RB), modulationschemes, and payload sizes. In this case, a CQI of a received signalhaving an error rate less than or equal to a predetermined value andhaving the largest payload size may be used as the downlink qualityinformation.

TABLE 3 Payload CQI No. RB Modulation size 0 25 QPSK 137 1 25 QPSK 173 225 16QAM 233 3 25 16QAM 317 . . . . . . . . . 30  25 64QAM 7168 

The SIR described above may be represented by an average in thefrequency domain and the time domain.

An average in the time domain may be calculated over an averaging perioddefined as a parameter. For example, an average may be calculated overan averaging period of 1 ms. Also, the average calculated over 1 ms maybe filtered using the following formula to obtain a value F_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 1 ms

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

Instead of averaging calculated values in the time domain as describedabove, calculated values may be averaged based on positional informationof the receiving apparatus 600. For example, the SIR may be obtained byaveraging SIRs over an averaging interval of 100 m, i.e., every 100-mmovement of the receiving apparatus 600. A two-dimensional parametersuch as 100 m² may be specified for the averaging interval instead of aone-dimensional parameter such as 100 m. The positional information isinput via the external input/output unit 610. The averaging intervalbased on the positional information may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

An average in the frequency domain may be calculated, as shown in FIG.7, over the entire system frequency band, or over a center frequencyband of 1.08 MHz located in the center of the system frequency band,i.e., including the center frequency of the system frequency band. InLTE, the center frequency band of 1.08 MHz is used to transmit asynchronization channel (SCH). An average may instead be calculated overeach resource block, or more flexibly, over any frequency band specifiedin the system frequency band. Further, as shown in FIG. 8, an averagemay be calculated over each resource block group including multipleresource blocks. In the example of FIG. 8, one resource block groupincludes five resource blocks. The averaging interval (or range) in thefrequency domain may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610.

If the SIR is to be calculated for each resource block or resource blockgroup, the highest M SIRs of resource blocks or resource block groupsmay be selected. The value M may be provided as a parameter in thereceiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

An expected downlink throughput may be calculated as described belowbased on the downlink quality information (channel quality indicator)calculated as described above.

TABLE 4 Throughput per resource CQI block [Mbps] 0 0.0 1 0.1 2 0.12 30.15 4 0.2 5 0.25 . . . . . . 30  60

For example, an expected downlink throughput is calculated based on alook-up table as shown by table 4 and the downlink quality information.Table 4 shows the correspondence between CQIs and throughputs [Mbps] perresource block. Table 4 is used to identify a throughput per resourceblock. Alternatively, a look-up table for identifying a throughput ofthe entire system frequency band or a throughput of a given frequencyband in the system frequency band may be used.

As described above, the downlink quality information may be representedby an average in the time domain and/or the frequency domain. Similarly,the expected downlink throughput may be represented by an average in thetime domain and/or the frequency domain. For example, the expecteddownlink throughput may be obtained by averaging throughputs in the timedomain over the averaging period and filtering the averaged throughputbased on the filtering factor “a”. Instead of averaging throughputs inthe time domain as described above, throughputs may be averaged based onpositional information of the receiving apparatus 600. For example, theexpected downlink throughput may be obtained by averaging throughputsover an averaging interval of 100 m, i.e., every 100-m movement of thereceiving apparatus 600. A two-dimensional parameter such as 100 m² maybe specified for the averaging interval instead of a one-dimensionalparameter such as 100 m. The positional information is input via theexternal input/output unit 610. The averaging interval based on thepositional information may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610.

An average in the frequency domain of the expected downlink throughputmay be calculated over the entire system frequency band, over a centerfrequency band of 1.08 MHz located in the center of the system frequencyband, i.e., including the center frequency of the system frequency band,over a given frequency band in the system frequency band, over eachresource block, or over each resource block group. If the expectedthroughput is to be calculated for each resource block or resource blockgroup, the highest M expected throughputs of resource blocks or resourceblock groups may be selected.

The averaging period in the time domain, the filtering factor “a”, theaveraging interval (or range) in the frequency domain, and the value Mmay be provided as parameters in the receiving apparatus 600 or may beinput from the outside via the external input/output unit 610.

The look-up tables of tables 2, 3, and 4 are just examples, and anyappropriate look-up tables containing different values may be used forthe calculations described above.

A method of calculating downlink quality information (channel qualityindicator) and a downlink throughput in a case where multiple inputmultiple output (MIMO) is employed for downlink is described below.

When MIMO is employed, the number of streams to be transmitted (i.e.,“rank”) varies depending on the radio quality of the propagationenvironment. For example, one stream is transmitted, for example, at theedge of a cell where the radio quality is poor; and two streams aretransmitted, for example, at the center of the cell where the radioquality is good. In this exemplary case, the mobile station calculatesan SIR or downlink quality information (channel quality indicator) andan expected throughput based on a downlink reference signal for each ofthe numbers of streams one and two, and reports the number of streamsthat provides the highest expected throughput to the base station 200.The base station 200 controls the number of streams for downlink basedon the number of streams reported from the mobile station. Whenclosed-loop MIMO is employed, the mobile station may report, in additionto the number of streams, an optimum precoding matrix to the basestation 200.

The number of streams is one or two when the number of transmittingantennas and the number of receiving antennas are two. Meanwhile, thenumber of streams is one, two, three, or four when the number oftransmitting antennas and the number of receiving antennas are four.

The downlink quality measuring unit 6087 may be configured to calculatethe number of streams (rank) in addition to downlink quality informationand an expected throughput. That is, when MIMO is employed, the downlinkquality measuring unit 6087 may be configured to calculate downlinkquality information, an expected throughput, and the number of streams(rank).

In addition to calculating the downlink quality information (channelquality indicator), the expected downlink throughput, and the number ofstreams (when MIMO is employed) based on the downlink reference signaltransmitted from the base station 200, those values may also becalculated based on a downlink reference signal transmitted from aneighboring base station. Also, if each base station covers multiplesectors, the above calculations may be performed based on downlinkreference signals transmitted from all sectors of the base station 200and the neighboring base station. Further, the downlink qualitymeasuring unit 6087 may be configured to calculate the downlink qualityinformation (channel quality indicator), the expected downlinkthroughput, and the number of streams (when MIMO is employed) based onreference signals from all base stations (or sectors) that the receivingapparatus 600 can receive. The downlink quality measuring unit 6087inputs the downlink quality information (channel quality indicator), theexpected downlink throughput, and the number of streams (when MIMO isemployed) to the external input/output unit 610.

The downlink quality information (channel quality indicator), theexpected downlink throughput, and the number of streams (when MIMO isemployed) input to the external input/output unit 610 are output, forexample, as graphs or numerical data to the outside (e.g., a monitorscreen or a storage medium) as described later. Also, the downlinkquality information (channel quality indicator), the expected downlinkthroughput, and the number of streams (when MIMO is employed) may beoutput, for example, as graphs or numerical data to the outside (e.g., amonitor screen or a storage medium) together with the positionalinformation of the receiving apparatus 600. Thus, the downlink qualityinformation (channel quality indicator) (i.e., radio quality of adownlink reference signal in a cell), the expected downlink throughput(i.e., expected throughput of a downlink shared channel), and the numberof streams (when MIMO is employed) are output to the outside and therebymade available to a network operator (or a user, a device, or so on). Inshort, the receiving apparatus 600 calculates the downlink qualityinformation (channel quality indicator), the expected downlinkthroughput, and the number of streams (when MIMO is employed) based on adownlink reference signal transmitted from the base station 200, andthereby makes it possible to evaluate downlink transmission efficiencyand radio capacity of the radio communication system 1000.

The delay profile measuring unit 6088 receives the channel estimate andthe downlink reference signal from the downlink reference signalreceiving unit 6085. The delay profile measuring unit 6088 calculates adownlink delay profile based on the received downlink reference signal.For example, the delay profile measuring unit 6088 calculates a delayprofile by performing IFFT processing on an FFT-processed referencesignal (channel estimate).

Alternatively, the delay profile measuring unit 6088 may be configuredto calculate a delay profile based on time correlation between adownlink received signal before FFT processing and an IFFT-processedtransmission sequence of a known reference signal. In this case, asshown in FIG. 9, a copy of a downlink received signal (before FFTprocessing) is input from the analog-to-digital conversion unit (A/D)6080 to the delay profile measuring unit 6088.

The delay profile may be represented by an average calculated over anaveraging period. The averaging period may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

Instead of averaging delay profiles in the time domain as describedabove, delay profiles may be averaged based on positional information ofthe receiving apparatus 600. For example, delay profiles may be averagedover an averaging interval of 100 m, i.e., every 100-m movement of thereceiving apparatus 600. A two-dimensional parameter such as 100 m² maybe specified for the averaging interval instead of a one-dimensionalparameter such as 100 m. The positional information is input via theexternal input/output unit 610. The averaging interval based on thepositional information may be provided as a parameter in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610. After calculating the delay profile, the delayprofile measuring unit 6088 calculates an expected (estimated) CPlength.

For example, as shown in FIG. 10, the delay profile measuring unit 6088selects paths with reception levels greater than or equal to apredetermined threshold from the paths constituting the delay profile,and calculates an expected CP length based on the time differencebetween the earliest-arriving path and the latest-arriving path in theselected paths. In E-UTRA, the length of a short cyclic prefix (CP) (mayalso be called a normal cyclic prefix) is 4.6875 μs and the length of along cyclic prefix (CP) is 16.6666 μs. In this case, the delay profilemeasuring unit 6088, for example, determines that the long CP is optimumif the time difference between the earliest-arriving path and thelatest-arriving path is greater than or equal to 4.6875 μs, anddetermines that the short CP is optimum if the time difference is lessthan 4.6875 μs.

Instead of calculating the expected CP length, the delay profilemeasuring unit 6088 may be configured to output the time differencebetween the earliest-arriving path and the latest-arriving path as anestimated propagation path delay. In this case, a user of acommunication area evaluation tool according to an embodiment of thepresent invention can easily determine whether the short CP or the longCP is optimum based on the estimated propagation path delay.

Alternatively, as shown in FIG. 11, the delay profile measuring unit6088 may be configured to define an FFT timing with respect to a pathwith the highest reception level and to calculate an expected CP lengthbased on a ratio of the reception level in a window defined by the FFTtiming and the short CP length to the reception level outside of thewindow. For example, the delay profile measuring unit 6088 may determinethat the short CP is optimum if the ratio of the reception level in thewindow to the reception level outside of the window is greater than orequal to 10, and determines that the long CP is optimum if the ratio isless than 10.

The threshold for selecting paths and the ratio of the reception levelin the window to the reception level outside of the window fordetermining the CP length may be provided as parameters in the receivingapparatus 600 or may be input from the outside via the externalinput/output unit 610. The threshold may be represented by an absolutevalue or a relative value. For example, the relative value may beindicated by a ratio of the received to the highest reception level.After calculations, the delay profile measuring unit 6088 inputs theexpected CP length or the estimated propagation path delay to theexternal input/output unit 610.

The expected CP length or the estimated propagation path delay input tothe external input/output unit 610 are output, for example, as graphs ornumerical data to the outside (e.g., a monitor screen or a storagemedium) as described later. Also, the expected CP length or theestimated propagation path delay may be output, for example, as graphsor numerical data to the outside (e.g., a monitor screen or a storagemedium) together with the positional information of the receivingapparatus 600. Thus, the expected CP length or the estimated propagationpath delay is output to the outside to allow a network operator (or auser, a device, or so on) to determine whether the CP length in the cellis appropriately set and to optimize parameters related to commonchannels such as the CP length for the cell 50.

The reference signal measuring unit 6089 receives the channel estimateand the downlink reference signal from the downlink reference signalreceiving unit 6085. Based on the channel estimate and the downlinkreference signal, the reference signal measuring unit 6089 calculates areceived power level of the downlink reference signal (reference signalreceived power (RSRP)), a downlink received carrier power level (E-UTRAcarrier received signal strength indicator (RSSI)) (may also be calleddownlink received power level), a value obtained by dividing thereceived power level of the downlink reference signal by the downlinkreceived carrier power level (RSRP/RSSI), and a path loss. The valueRSRP/RSSI may also be called reference signal received quality (RSRQ).

Here, the downlink received carrier power level is a sum of receivedpower levels of all signals from the serving cell, i.e., the basestation 200, received power levels of signals from all base stations inneighboring cells, received power levels of interference signals fromneighboring frequencies, a thermal noise power level, and so on. See,for example, 3GPP TS36.214, v 1.0.0, 2007-05, for definitions of thereference signal received power (RSRP) and the E-UTRA carrier receivedsignal strength indicator (RSSI).

The path loss is calculated based on the received power level of thedownlink reference signal and the transmission power level of thedownlink reference signal at the base station 200 as follows:Path loss [dB]=(transmission power level of downlink referencesignal)−(received power level of downlink reference signal)

The transmission power level of the downlink reference signal may beprovided as a parameter in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610. Also, thetransmission power level of the downlink reference signal may bedetermined based on the information regarding the transmission powerlevel of the downlink reference signal obtained from the P-BCH or theD-BCH. The information regarding the transmission power level of thedownlink reference signal obtained from the P-BCH or the D-BCH is inputfrom the data signal decoding unit 6084.

Meanwhile, if the receiving apparatus 600 includes two receivingantennas, the reception power level of the downlink reference signal andthe downlink received carrier power level may be measured in one of thefollowing three methods:

(1) Using a value measured at one of the two antennas (main antenna).

(2) Using an average of values measured at the two antennas.

(3) Using the sum of values measured at the two antennas.

The same method or different methods may be used for measuring thereception power level of the downlink reference signal and the downlinkreceived carrier power level. In this case, the value RSRP/RSSI isobtained by dividing the received power level of the downlink referencesignal by the downlink received carrier power level measured in one ofthe above three methods. Also, the path loss is calculated based on thereceived power level of the downlink reference signal calculated in oneof the above three methods. The three methods may be provided asparameters in the receiving apparatus 600 or may be input from theoutside via the external input/output unit 610.

The received power level of the downlink reference signal, the downlinkreceived carrier power level, the value RSRP/RSSI, and the path loss maybe represented by averages in the frequency domain and/or the timedomain.

An average in the time domain may be calculated over an averaging perioddefined as a parameter. For example, an average may be calculated overan averaging period of 200 ms. Also, the average calculated over 200 msmay be filtered using the following formula to obtain a value F_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 200 ms

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

Instead of averaging calculated values in the time domain as describedabove, calculated values may be averaged based on positional informationof the receiving apparatus 600. For example, the received power level ofthe downlink reference signal, the downlink received carrier powerlevel, the value RSRP/RSSI, and the path loss may be obtained byaveraging calculated values over an averaging interval of 100 m, i.e.,every 100-m movement of the receiving apparatus 600. A two-dimensionalparameter such as 100 m² may be specified for the averaging intervalinstead of a one-dimensional parameter such as 100 m. The positionalinformation is input via the external input/output unit 610. Theaveraging interval based on the positional information may be providedas a parameter in the receiving apparatus 600 or may be input from theoutside via the external input/output unit 610.

An average in the frequency domain may be calculated, as shown in FIG.7, over the entire system frequency band, or over a center frequencyband of 1.08 MHz located in the center of the system frequency band,i.e., including the center frequency of the system frequency band. InLTE, the center frequency band of 1.08 MHz is used to transmit asynchronization channel (SCH). An average may instead be calculated overeach resource block, or more flexibly, over any frequency band specifiedin the system frequency band. Further, as shown in FIG. 8, an averagemay be calculated over each resource block group including multipleresource blocks. In the example of FIG. 8, one resource block groupincludes five resource blocks. Also, instead of an average, a sum ofcalculated values in a frequency domain may be used. The averaginginterval (or range) in the frequency domain may be provided as aparameter in the receiving apparatus 600 or may be input from theoutside via the external input/output unit 610. Also, a parameterindicating whether to use an average or a sum may be provided in thereceiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

In addition to calculating the received power level of the downlinkreference signal, the downlink received carrier power level, the valueRSRP/RSSI, and the path loss based on the downlink reference signaltransmitted from the base station 200, those values may also becalculated based on a downlink reference signal transmitted from aneighboring base station. Also, if each base station covers multiplesectors, the above calculations may be performed based on downlinkreference signals transmitted from all sectors of the base station 200and the neighboring base station. Further, the reference signalmeasuring unit 6089 may be configured to calculate the received powerlevel of the downlink reference signal, the downlink received carrierpower level, the value RSRP/RSSI, and the path loss based on referencesignals from all base stations (or sectors) that the receiving apparatus600 can receive.

After calculations, the reference signal measuring unit 6089 inputs thereceived power level of the downlink reference signal, the downlinkreceived carrier power level, the value RSRP/RSSI, and the path loss tothe external input/output unit 610.

The received power level of the downlink reference signal, the downlinkreceived carrier power level, the value RSRP/RSSI, and the path lossinput to the external input/output unit 610 are output, for example, asgraphs or numerical data to the outside (e.g., a monitor screen or astorage medium) as described later. Also, the received power level ofthe downlink reference signal, the downlink received carrier powerlevel, the value RSRP/RSSI, and the path loss may be output, forexample, as graphs or numerical data to the outside (e.g., a monitorscreen or a storage medium) together with the positional information ofthe receiving apparatus 600. Thus, the received power level of thedownlink reference signal, the downlink received carrier power level,the value RSRP/RSSI, and the path loss are output to the outside toallow a network operator (or a user, a device, or so on) to determinethe radio quality of a downlink reference signal in a cell. Generally,the received power level of the downlink reference signal, the downlinkreceived carrier power level, the value RSRP/RSSI, and the path loss areused for mobile control such as handover and cell reselection. In short,the receiving apparatus 600 calculates the received power level of thedownlink reference signal, the downlink received carrier power level,the value RSRP/RSSI, and the path loss for all base stations from whichthe receiving apparatus 600 can receive signals, and thereby makes itpossible to evaluate mobile control characteristics of the radiocommunication system 1000.

The error rate obtaining unit 6090 receives the decoding results of theP-BCH, the D-BCH, the downlink scheduling information for the D-BCH, thePI, and the PCH from the data signal decoding unit 6084, and calculatestheir error rates. A measuring period for calculating the error rates isreceived from the external input/output unit 610. For example, if themeasuring period received from the external input/output unit 610indicates one second, the error rate obtaining unit 6090 calculateserror rates of the P-BCH, the D-BCH, the downlink scheduling informationfor the D-BCH, the PI, and the PCH every one second. After calculations,the error rate obtaining unit 6090 inputs the error rates of the P-BCH,the D-BCH, the downlink scheduling information for the D-BCH, the PI,and the PCH to the external input/output unit 610.

Instead of calculating error rates every measuring period as describedabove, error rates may be calculated every measuring interval based onpositional information of the receiving apparatus 600. For example, theerror rates of the P-BCH, the D-BCH, the downlink scheduling informationfor the D-BCH, the PI, and the PCH may be calculated every measuringinterval of 100 m, i.e., every 100-m movement of the receiving apparatus600. A two-dimensional parameter such as 100 m² may be specified for themeasuring interval instead of a one-dimensional parameter such as 100 m.The positional information is input via the external input/output unit110. The measuring interval based on the positional information may beprovided as a parameter in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

The error rates of the P-BCH, the D-BCH, the downlink schedulinginformation for the D-BCH, the PI, and the PCH input to the externalinput/output unit 610 are output, for example, as graphs or numericaldata to the outside (e.g., a monitor screen or a storage medium) asdescribed later. Also, the error rates of the P-BCH, the D-BCH, thedownlink scheduling information for the D-BCH, the PI, and the PCH maybe output, for example, as graphs or numerical data to the outside(e.g., a monitor screen or a storage medium) together with thepositional information of the receiving apparatus 600. Thus, the errorrates of the P-BCH, the D-BCH, the downlink scheduling information forthe D-BCH, the PI, and the PCH are output to the outside to allow anetwork operator (or a user, a device, or so on) to determine whetherthe quality of the common channels is appropriately maintained and tooptimize parameters related to the common channels such as thetransmission power and the number of resource elements allocated to thecommon channels. Instead of the number of resource elements, the numberof resource blocks, the number of subcarriers, or the number of OFDMsymbols may be optimized based on the error rates.

In the above descriptions with reference to FIGS. 5 and 6, receptionprocessing of a downlink signal transmitted from the base station 200 ismainly discussed. However, the receiving apparatus 600 can also performsimilar reception processing for a downlink signal transmitted from aneighboring base station.

The external input/output unit 610 outputs calculated (measured) valuesreceived from the uplink quality measuring unit 6086, the downlinkquality measuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090 of the baseband signal processing unit 608 to external interfaces.For example, the external input/output unit 610 displays the calculatedvalues as numerical data and/or graphs on a monitor screen or stores thecalculated values as numerical data in a storage medium such as a memoryor a hard disk.

Also, the external input/output unit 610 may obtain positionalinformation of the receiving apparatus 600 and output calculated(measured) values received from the uplink quality measuring unit 6086,the downlink quality measuring unit 6087, the delay profile measuringunit 6088, the reference signal measuring unit 6089, and the error rateobtaining unit 6090 to an external interface (e.g., a monitor screen ora storage medium) together with the positional information. Thepositional information may be obtained, for example, from a positionalinformation obtaining device such as a GPS 700 connected to the externalinput/output unit 610.

When output together with the positional information, the calculatedvalues from the uplink quality measuring unit 6086, the downlink qualitymeasuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090 may be represented by averages in the time domain or averagescalculated based on the positional information.

Also, when the calculated values are averaged based on the positionalinformation instead of in the time domain by the uplink qualitymeasuring unit 6086, the downlink quality measuring unit 6087, the delayprofile measuring unit 6088, the reference signal measuring unit 6089,and the error rate obtaining unit 6090, the positional information isobtained by the GPS 700 and input via the external input/output unit 610to the respective units.

The external input/output unit 610 may also be configured to storeparameters used by the uplink quality measuring unit 6086, the downlinkquality measuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090, and to input the parameters to the corresponding units. Theparameters may be stored as internal parameters of the receivingapparatus 600 or may be input from an external interface. Details of theparameters are given in the above descriptions.

Next, data obtaining processes (methods) performed by the receivingapparatus 600 of this embodiment are described with reference to FIGS.12 and 13. Below, a data obtaining process is described with referenceto FIG. 12 and another data obtaining process where calculated valuesare averaged based on positional information is described with referenceto FIG. 13.

Referring to FIG. 12, the receiving apparatus 600 receives a downlinkreference signal transmitted from the base station 200 (step S1202).

Based on the received downlink reference signal, the receiving apparatus600 calculates at least one of uplink quality, downlink quality, a delayprofile, a reference signal measurement, and an error rate (step S1204).For example, the uplink quality measuring unit 6086, the downlinkquality measuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090 of the baseband signal processing unit 608 may retain parametersand calculate expected values based on the parameters and the downlinkreference signal.

Then, the receiving apparatus 600 outputs at least one of the uplinkquality, the downlink quality, the delay profile, the reference signalmeasurement, and the error rate calculated in step S1204 to an externalinterface such as a monitor screen or a storage medium (step S1206).

This makes it possible for a network operator (or a user, a device, orso on) to obtain at least one of the uplink quality, the downlinkquality, the delay profile, the reference signal measurement, and theerror rate output from the receiving apparatus 600. The expected valuesmay be represented by averages in the time domain.

A data obtaining process where calculated values are averaged based onpositional information is described below with reference to FIG. 13.

The receiving apparatus 600 receives a downlink reference signaltransmitted from the base station 200 (step S1302).

Based on the received downlink reference signal, the receiving apparatus600 calculates at least one of uplink quality, downlink quality, a delayprofile, a reference signal measurement, and an error rate (step S1304).For example, the uplink quality measuring unit 6086, the downlinkquality measuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090 of the baseband signal processing unit 608 may retain parametersand calculate expected values based on the parameters and the downlinkreference signal.

Positional information obtained by the GPS 700 is input via the externalinput/output unit 610 to the uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, the delay profile measuring unit6088, the reference signal measuring unit 6089, and the error rateobtaining unit 6090. The uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, the delay profile measuring unit6088, the reference signal measuring unit 6089, and/or the error rateobtaining unit 6090 output the calculated values together with thepositional information (step S1306).

Then, the receiving apparatus 600 outputs at least one of the uplinkquality, the downlink quality, the delay profile, the reference signalmeasurement, and the error rate calculated in step S1304 together withthe positional information to an external interface such as a monitorscreen or a storage medium (step S1308).

This makes it possible for a network operator (or a user, a device, orso on) to obtain at least one of the uplink quality, the downlinkquality, the delay profile, the reference signal measurement, and theerror rate represented by averages calculated based on the positionalinformation.

Other data obtaining processes (methods) performed by the receivingapparatus 600 of this embodiment are described with reference to FIGS.14 and 15. Here, it is assumed that the receiving apparatus 600communicates with the base station 200 and measures a throughput basedon downlink scheduling information or an uplink scheduling grant. Below,a data obtaining process is described with reference to FIG. 14, andanother data obtaining process where calculated values are averagedbased on positional information is described with reference to FIG. 15.

The receiving apparatus 600 communicates with the base station 200 (stepS1402).

The receiving apparatus 600 receives downlink scheduling information oran uplink scheduling grant transmitted from the base station 200 (stepS1404).

Based on the received downlink scheduling information or uplinkscheduling grant, the receiving apparatus 600 calculates at least one ofa downlink throughput and an uplink throughput (step S1406).

Then, the receiving apparatus 600 outputs at least one of the downlinkthroughput and the uplink throughput calculated in step S1406 to anexternal interface such as a monitor screen or a storage medium (stepS1408).

This makes it possible for a network operator (or a user, a device, orso on) to obtain at least one of the downlink throughput and the uplinkthroughput output from the receiving apparatus 600. The downlinkthroughput and the uplink throughput may be represented by averages inthe time domain.

A data obtaining process where calculated values are averaged based onpositional information is described below with reference to FIG. 15.

The receiving apparatus 600 communicates with the base station 200 (stepS1502).

The receiving apparatus 600 receives downlink scheduling information oran uplink scheduling grant transmitted from the base station 200 (stepS1504).

Based on the received downlink scheduling information or uplinkscheduling grant, the receiving apparatus 600 calculates at least one ofa downlink throughput and an uplink throughput (step S1506).

Positional information obtained by the GPS 700 is input via the externalinput/output unit 610 to the uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, the delay profile measuring unit6088, the reference signal measuring unit 6089, and the error rateobtaining unit 6090. The uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, the delay profile measuring unit6088, the reference signal measuring unit 6089, and/or the error rateobtaining unit 6090 output calculated values together with thepositional information (step S1508).

Then, the receiving apparatus 600 outputs at least one of the downlinkthroughput and the uplink throughput calculated in step S1506 togetherwith the positional information to an external interface such as amonitor screen or a storage medium (step S1510).

This makes it possible for a network operator (or a user, a device, orso on) to obtain at least one of the downlink throughput and the uplinkthroughput that is represented by an average calculated based on thepositional information.

This embodiment makes it possible to obtain values such as an expecteddownlink throughput and an expected uplink throughput to be used by anetwork operator for cell design, and thereby makes it possible toconstruct a high-quality, highly-efficient network.

Second Embodiment

A receiving apparatus for communication area evaluation according toanother embodiment of the present invention is described below.

In this embodiment, it is assumed that multiple base stations in theradio communication system 1000 perform downlink transmission insynchronization with each other. A network where multiple base stationsperform downlink transmission in synchronization with each other(hereafter, such base stations may be called“downlink-transmission-synchronized base stations”) is called a singlefrequency network (SFN) or a multicast/broadcast over single frequencynetwork (MBSFN).

In the MBSFN, when, for example, the same signal is transmitted frommultiple downlink-transmission-synchronized base stations, the mobilestation can comparatively easily combine multiple instances of thesignal transmitted from the base stations. This in turn makes itpossible to improve the transmission efficiency and the transmissionrate. This technology is particularly effective in multicast andbroadcast transmission where a common signal is transmitted from basestations to an unspecified number of mobile stations.

A radio communication system 1000 including a receiving apparatus 600and base stations 200 of this embodiment is described below withreference to FIG. 16.

The radio communication system 1000 is based on, for example, EvolvedUTRA and UTRAN. The radio communication system 1000 includes the basestations 200 _(m) (200 ₁, 200 ₂, 200 ₃, 200 ₄, 200 ₅, 200 ₆, 200 ₇, . .. , 200 _(m); where m is an integer greater than 0), mobile stations 100_(n) (100 ₁, 100 ₂, 100 ₃ . . . 100 _(n); where n is an integer greaterthan 0), and the receiving apparatus 600 located in one of cells 50 _(l)(50 ₁, 50 ₂, 50 ₃, . . . , 50 _(l); where l is an integer greater than0) that are areas where mobile communication services are provided bythe base stations 200 _(m).

In FIG. 16, for brevity, only one sector is shown for each of the basestations 200 _(m). However, each of the base stations 200 _(m) may havetwo or more sectors.

The receiving apparatus 600 may or may not be communicating with thebase stations 200 _(m) based on Evolved UTRA and UTRAN. When thereceiving apparatus 600 communicates with the base stations 200 _(m)based on Evolved UTRA and UTRAN, communication processing similar tothat performed between the mobile stations 100 _(n) and the basestations 200 _(m) is performed between the receiving apparatus 600 andthe base stations 200 _(m).

The receiving apparatus 600 of this embodiment has substantially thesame configuration as that of the first embodiment except theconfiguration of the baseband signal processing unit 108. Therefore, thebaseband signal processing unit 108 of this embodiment is mainlydescribed below.

As shown in FIG. 17, the baseband signal processing unit 108 of thereceiving apparatus 600 of this embodiment includes an analog-to-digitalconversion unit (A/D) 6080, a CP removing unit 6081, a fast Fouriertransform unit (FFT) 6082, a demultiplexing unit (DeMUX) 6083, a datasignal decoding unit 6084, a downlink reference signal receiving unit6085, a downlink quality measuring unit 6087, a delay profile measuringunit 6088, a reference signal measuring unit 6089, and an error rateobtaining unit 6090.

The functions of the analog-to-digital conversion unit (A/D) 6080, theCP removing unit 6081, the fast Fourier transform unit (FFT) 6082, andthe demultiplexing unit (DeMUX) 6083 are substantially the same as thoseof the first embodiment. In the second embodiment, unlike the firstembodiment where a downlink signal transmitted from one base station isinput from the transceiver unit 606, a downlink signal input from thetransceiver unit 606 includes signals transmitted from multipledownlink-transmission-synchronized base stations. Here, it is assumedthat the receiving apparatus 600 cannot identify base stationstransmitting signals included in the downlink signal.

The data signal decoding unit 6084 receives a channel estimate from thedownlink reference signal receiving unit 6085, and applies channelcompensation based on the channel estimate to a downlink data signaltransmitted from multiple downlink-transmission-synchronized basestations to decode the data signal. Here, the data signal indicates acommon channel signal transmitted from thedownlink-transmission-synchronized base stations. The common channelsignal, for example, includes common channels such as a P-BCH, a D-BCH,a broadcast channel, and a multicast channel. After decoding the datasignal, the data signal decoding unit 6084 reports the decoding resultsto the error rate obtaining unit 6090.

Also, the data signal decoding unit 6084 obtains information in theP-BCH and the D-BCH, and inputs the obtained information to relevantcomponents of the receiving apparatus 600 as needed. For example, thedata signal decoding unit 6084 obtains information regarding thetransmission power level of a downlink reference signal from the P-BCHor the D-BCH, and inputs the obtained information to the referencesignal measuring unit 6089.

The downlink reference signal receiving unit 6085 performs channelestimation based on the downlink reference signal and determines channelcompensation to be applied to the received data signal. In other words,the downlink reference signal receiving unit 6085 calculates a channelestimate. The downlink reference signal receiving unit 6085 inputs thecalculated channel estimate to the data signal decoding unit 6084. Thedownlink reference signal receiving unit 6085 also inputs the downlinkreference signal and the channel estimate to the downlink qualitymeasuring unit 6087, the delay profile measuring unit 6088, thereference signal measuring unit 6089, and the error rate obtaining unit6090. Here, it is assumed that the downlink reference signal istransmitted from the multiple downlink-transmission-synchronized basestations.

The functions of the downlink quality measuring unit 6087, the delayprofile measuring unit 6088, and the reference signal measuring unit6089 are substantially the same as those of the first embodiment, andtherefore descriptions of those functions are omitted here. In thesecond embodiment, unlike the first embodiment where a downlinkreference signal transmitted from one base station is input from thedownlink reference signal receiving unit 6085, the downlink referencesignal input from the downlink reference signal receiving unit 6085 istransmitted from multiple downlink-transmission-synchronized basestations.

The error rate obtaining unit 6090 receives decoding results of theP-BCH, the D-BCH, the multicast channel, and the broadcast channel fromthe data signal decoding unit 6084, and calculates their error rates. Ameasuring period for calculating the error rates is received from theexternal input/output unit 610. For example, if the measuring periodreceived from the external input/output unit 610 indicates one second,the error rate obtaining unit 6090 calculates error rates of the P-BCH,the D-BCH, the multicast channel, and the broadcast channel every onesecond. After calculations, the error rate obtaining unit 6090 inputsthe error rates of the P-BCH, the D-BCH, the multicast channel, and thebroadcast channel to the external input/output unit 610.

Instead of calculating error rates every measuring period as describedabove, error rates may be calculated every measuring interval based onpositional information of the receiving apparatus 600. For example, theerror rates of the P-BCH, the D-BCH, the multicast channel, and thebroadcast channel may be calculated every measuring interval of 100 m,i.e., every 100-m movement of the receiving apparatus 600. Atwo-dimensional parameter such as 100 m² may be specified for themeasuring interval instead of a one-dimensional parameter such as 100 m.The positional information is input via the external input/output unit610. The measuring interval based on the positional information may beprovided as a parameter in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

The error rates of the P-BCH, the D-BCH, the multicast channel, and thebroadcast channel input to the external input/output unit 610 areoutput, for example, as graphs or numerical data to the outside (e.g., amonitor screen or a storage medium). Also, the error rates of the P-BCH,the D-BCH, the multicast channel, and the broadcast channel may beoutput, for example, as graphs or numerical data to the outside (e.g., amonitor screen or a storage medium) together with the positionalinformation of the receiving apparatus 600. Thus, the error rates of theP-BCH, the D-BCH, the multicast channel, and the broadcast channel areoutput to the outside to allow a network operator (or a user, a device,or so on) to determine whether the quality of the common channels isappropriately maintained and to optimize parameters related to thecommon channels such as the transmission power and the number ofresource elements allocated to the common channels. Instead of thenumber of resource elements, the number of resource blocks, the numberof subcarriers, or the number of OFDM symbols may be optimized based onthe error rates.

Third Embodiment

In the first embodiment, basically, the receiving apparatus 600 receivesa downlink reference signal, performs various measurements andcalculations, and outputs the results to an external interface.

With the receiving apparatus 600 of the first embodiment, however, it isdifficult to accurately calculate the received SIR of an uplink signalat the base station 200 and therefore it is difficult to accuratelycalculate an expected uplink throughput. Also, since the receivingapparatus 600 of the first embodiment is not informed of the operationsof a scheduler (MAC processing unit) of the base station 200, theexpected downlink throughput calculated by the receiving apparatus 600may not always match the actual downlink throughput.

In this embodiment, to solve or reduce the above problems, the receivingapparatus 600 establishes a connection with the base station 200 andperforms uplink and downlink communications with the base station 200.This configuration makes it possible to accurately calculate an expecteduplink throughput and an expected downlink throughput. Moreparticularly, the receiving apparatus 600 of this embodiment receivesthe uplink scheduling grant and the downlink scheduling information fromthe base station 200 and calculates an expected uplink throughput and anexpected downlink throughput based on the received uplink schedulinggrant and downlink scheduling information.

The uplink scheduling grant, for example, includes information regardingan uplink shared channel such as uplink resource allocation information,a UE ID(s), a data size(s), a modulation scheme(s), uplink transmissionpower information, and information regarding a demodulation referencesignal used in uplink MIMO. Receiving the uplink scheduling grant makesit possible to calculate an expected uplink throughput based on theuplink resource allocation information and the data size.

The downlink scheduling information, for example, includes informationregarding a downlink shared channel such as downlink resource blockallocation information, a UE ID(s), the number of streams, informationregarding a precoding vector(s), a data size(s), a modulation scheme(s),and information regarding hybrid automatic repeat request (HARQ).Receiving the downlink scheduling information makes it possible tocalculate an expected downlink throughput based on the downlink resourceblock allocation information, the data size, and the number of streams.

Details of the third embodiment are described below.

The base station 200 of this embodiment has substantially the sameconfiguration as that of the first embodiment, and therefore itsdescriptions are omitted here.

A receiving apparatus 600 of this embodiment is described below withreference to FIG. 18. The receiving apparatus 600 of this embodimentestablishes a connection and communicates with the base station 200, andthereby calculates and outputs uplink and downlink communicationquality. This feature of the receiving apparatus 600 is mainly discussedbelow.

As shown in FIG. 18, the receiving apparatus 600 of this embodimentincludes an antenna 602, an amplifier 604, a transceiver unit 606, abaseband signal processing unit 608, an external input/output unit 610,a call processing unit 612, and an application unit 614.

The antenna 602, the amplifier 604, and the transceiver unit 606 of thisembodiment have substantially the same configurations and functions asthose of the first embodiment, and therefore their descriptions areomitted here.

A configuration of the baseband signal processing unit 608 of thisembodiment is described below with reference to FIG. 19.

The baseband signal processing unit 608 includes an analog-to-digitalconversion unit (A/D) 6080, a CP removing unit 6081, an FFT 6082, aDeMUX 6083, a data signal decoding unit 6084, a downlink referencesignal receiving unit 6085, an uplink quality measuring unit 6086, adownlink quality measuring unit 6087, a reference signal measuring unit6089, a MAC processing unit 6091, an RLC processing unit 6092, a signalgenerating unit 6093, and a transmission processing unit 6094.

The analog-to-digital conversion unit (A/D) 6080 converts an analogbaseband signal input from the transceiver unit 606 into a digitalsignal and inputs the digital signal to the CP removing unit 6081.

The CP removing unit 6081 removes CPs from received symbols and inputsremaining effective symbols to the FFT 6082.

The fast Fourier transform unit (FFT) 6082 fast-Fourier-transforms theinput signal and thereby OFDM-demodulates the signal, and inputs thedemodulated signal to the DeMUX 6083.

The demultiplexing unit (DeMUX) 6083 separates a downlink referencesignal, a broadcast channel signal, a downlink control channel signal,and a downlink shared channel signal from the demodulated signal, inputsthe downlink reference signal to the downlink reference signal receivingunit 6085, and inputs the broadcast channel signal, the downlink controlchannel signal, and the downlink shared channel signal to the datasignal decoding unit 6084.

The downlink reference signal receiving unit 6085 performs channelestimation based on the downlink reference signal and determines channelcompensation to be applied to a received downlink data signal. In otherwords, the downlink reference signal receiving unit 6085 calculates achannel estimate. The downlink reference signal receiving unit 6085inputs the calculated channel estimate to the data signal decoding unit6084. The downlink reference signal receiving unit 6085 also inputs thedownlink reference signal and the channel estimate to the uplink qualitymeasuring unit 6086, the downlink quality measuring unit 6087, and thereference signal measuring unit 6089.

The data signal decoding unit 6084 receives the channel estimate fromthe downlink reference signal receiving unit 6085, and applies channelcompensation based on the channel estimate to the downlink data signalreceived from the base station 200 to decode the downlink data signal.Here, the data signal includes the broadcast channel signal, thedownlink control channel signal, and the downlink shared channel signaltransmitted from the base station 200. The broadcast channel signalincludes broadcast channels such as the P-BCH and the D-BCH. Thedownlink control channel signal includes downlink control channels suchas the downlink scheduling information, the uplink scheduling grant, andacknowledgement information for an uplink shared channel. After decodingthe data signal, the data signal decoding unit 6084 reports the decodingresults to the uplink quality measuring unit 6086, the downlink qualitymeasuring unit 6087, and the MAC processing unit 6091.

Also, the data signal decoding unit 6084 obtains information from theP-BCH and the D-BCH, and inputs the obtained information to relevantcomponents of the receiving apparatus 600 as needed. For example, thedata signal decoding unit 6084 may obtain information regarding thetransmission power level of the downlink reference signal from the P-BCHor the D-BCH, and input the obtained information to the uplink qualitymeasuring unit 6086 and the reference signal measuring unit 6089. Asanother example, the data signal decoding unit 6084 may obtaininformation (P0) regarding uplink transmission power control from theP-BCH or the D-BCH, and input the obtained information to the uplinkquality measuring unit 6086.

The uplink quality measuring unit 6086 receives the channel estimate andthe downlink reference signal from the downlink reference signalreceiving unit 6085, and receives the decoding results of the downlinkdata signal from the data signal decoding unit 6084.

Below, functions of the uplink quality measuring unit 6086 of thisembodiment not included in the uplink quality measuring unit 6086 of thefirst embodiment are described.

The uplink quality measuring unit 6086 calculates an expected uplinkthroughput based on the uplink resource allocation information and thedata size obtained from the uplink scheduling grant in the data signal.The uplink resource allocation information indicates frequency resourceallocation information. For example, the uplink quality measuring unit6086 calculates an expected throughput per resource block as follows:Expected throughput [bits/second]=data size [bits]×1000/number ofresource blocks

Here, it is assumed that one subframe is 1 ms and therefore the datasize is multiplied by 1000.

As in the first embodiment, the expected uplink throughput may berepresented by an average in the time domain and/or the frequencydomain. Also, the expected uplink throughput may be represented by anaverage calculated based on positional information.

Instead of calculating an expected throughput per resource block as inthe above example, an expected throughput may be calculated based onresource allocation information in the frequency domain and/or the timedomain. For example, an expected throughput may be calculated based onthe frequency (or the rate) at which the uplink scheduling grant isactually transmitted and an actually-allocated transmission band, orbased on an assumption that all frequency and time resources areallocated to the receiving apparatus 600. Further, an expectedthroughput may be calculated based on hypothetical frequency and timeresources (allocation frequency) input from the outside via the externalinput/output unit 610.

In this embodiment, as described above, the receiving apparatus 600 isin communication with the base station 200. Therefore, the uplinkquality measuring unit 6086 may set “delta_mcs” in the above formula forcalculating the expected uplink transmission power level at a valuereported via an RRC message. Also in the formula, “delta_i” may be setat a value reported via the uplink scheduling grant.

The downlink quality measuring unit 6087 receives the channel estimateand the downlink reference signal from the downlink reference signalreceiving unit 6085, and receives the decoding results of the downlinkdata signal from the data signal decoding unit 6084.

Below, functions of the downlink quality measuring unit 6087 of thisembodiment not included in the downlink quality measuring unit 6087 ofthe first embodiment are described.

The downlink quality measuring unit 6087 calculates an expected downlinkthroughput based on the downlink resource block allocation information,the data size, and the number of streams obtained from the downlinkscheduling information in the data signal. For example, the downlinkquality measuring unit 6087 calculates an expected throughput perresource block as follows:Expected throughput [bits/second]=data size [bits]×1000/number ofresource blocks

Here, it is assumed that one subframe is 1 ms and therefore the datasize is multiplied by 1000.

As in the first embodiment, the expected downlink throughput may berepresented by an average in the time domain and/or the frequencydomain. Also, the expected downlink throughput may be represented by anaverage calculated based on positional information.

Instead of calculating an expected throughput per resource block as inthe above example, an expected throughput may be calculated based onresource allocation information in the frequency domain and/or the timedomain. For example, an expected throughput may be calculated based onthe frequency (or the rate) at which the downlink scheduling informationis actually transmitted and an actually-allocated transmission band, orbased on an assumption that all frequency and time resources areallocated to the receiving apparatus 600. Further, an expectedthroughput may be calculated based on hypothetical frequency and timeresources (allocation frequency) input from the outside via the externalinput/output unit 610.

The reference signal measuring unit 6089 of this embodiment issubstantially the same as that of the first embodiment except thedifference as described below.

For a downlink reference signal from the serving cell, i.e., the basestation 200, and a neighboring base station, the reference signalmeasuring unit 6089 calculates a received power level of the downlinkreference signal (reference signal received power (RSRP)), a downlinkreceived carrier power level (E-UTRA carrier received signal strengthindicator (RSSI)), a value obtained by dividing the received power levelof the downlink reference signal by the downlink received carrier powerlevel (RSRP/RSSI), and a path loss, and inputs the calculated values tothe call processing unit 612.

The MAC processing unit 6091 receives the downlink schedulinginformation, the uplink scheduling grant, the acknowledgementinformation for an uplink shared channel, and the downlink sharedchannel from the data signal decoding unit 6084.

The MAC processing unit 6091, based on the uplink scheduling grant,performs transmission processing such as transport format determinationand MAC-layer retransmission control (HARQ) for the uplink user data.Specifically, if transmission using an uplink shared channel isrequested by the uplink scheduling grant received from the base station200 via the data signal decoding unit 6084, the MAC processing unit 6091performs transmission processing such as transport format determinationand retransmission control (HARQ) for packet data in a data buffer ofthe receiving apparatus 600, and inputs the packet data to the signalgenerating unit 6093.

For downlink, the MAC processing unit 6091 performs, for example,reception processing in MAC-layer retransmission control for downlinkpacket data based on the downlink scheduling information from the datasignal decoding unit 6084.

Also, the MAC processing unit 6091 may be configured to measure uplinkand downlink MAC layer throughputs and to input the measured throughputsto the external input/output unit 610.

The MAC layer throughputs may be represented by averages in the timedomain. An average in the time domain may be calculated over anaveraging period defined as a parameter. For example, an average may becalculated over an averaging period of 1 s. Also, the average calculatedover 1 s may be filtered using the following formula to obtain a valueF_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 1 s

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

Instead of averaging throughputs in the time domain as described above,throughputs may be averaged based on positional information of thereceiving apparatus 600. For example, MAC layer throughputs may beaveraged over an averaging interval of 100 m, i.e., every 100-m movementof the receiving apparatus 600. A two-dimensional parameter such as 100m² may be specified for the averaging interval instead of aone-dimensional parameter such as 100 m. The positional information isinput via the external input/output unit 610. The averaging intervalbased on the positional information may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

Also, the MAC processing unit 6091 may be configured to calculate a MAClayer throughput based on resource allocation information in thefrequency domain and/or the time domain. That is, the MAC processingunit 6091 may calculate an actual MAC layer throughput or calculate aMAC layer throughput based on an assumption that all frequency and timeresources are allocated to the receiving apparatus 600. Also, the MACprocessing unit 6091 may calculate a MAC layer throughput based onhypothetical frequency and time resources (allocation frequency) inputfrom the outside via the external input/output unit 610.

After calculations, the MAC processing unit 6091 inputs the calculatedMAC layer throughputs to the external input/output unit 610.

The RLC (radio link control) processing unit 6092 performs, for uplink,RLC layer transmission processing such as segmentation/concatenation ofpacket data and transmission processing in RLC retransmission control,and performs, for downlink, RLC layer reception processing such assegmentation/concatenation of packet data and reception processing inRLC retransmission control. The RLC processing unit 6092 may beconfigured to perform PDCP layer processing in addition to the RLC layerprocessing described above.

Also, the RLC processing unit 6092 may be configured to measure uplinkand downlink RLC layer throughputs and to input the measured throughputsto the external input/output unit 610.

The RLC layer throughputs may be represented by averages in the timedomain.

An average in the time domain may be calculated over an averaging perioddefined as a parameter. For example, an average may be calculated overan averaging period of 1 s. Also, the average calculated over 1 s may befiltered using the following formula to obtain a value F_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 1 s

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 610.

Instead of averaging throughputs in the time domain as described above,throughputs may be averaged based on positional information of thereceiving apparatus 600. For example, RLC layer throughputs may beaveraged over an averaging interval of 100 m, i.e., every 100-m movementof the receiving apparatus 600. A two-dimensional parameter such as 100m² may be specified for the averaging interval instead of aone-dimensional parameter such as 100 m. The positional information isinput via the external input/output unit 610. The averaging intervalbased on the positional information may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

Also, the RLC processing unit 6092 may be configured to calculate an RLClayer throughput based on resource allocation information in thefrequency domain and/or the time domain. That is, the RLC processingunit 6091 may calculate an actual RLC layer throughput or calculate anRLC layer throughput based on an assumption that all frequency and timeresources are allocated to the receiving apparatus 600. Also, the RLCprocessing unit 6092 may calculate an RLC layer throughput based onhypothetical frequency and time resources (allocation frequency) inputfrom the outside via the external input/output unit 610.

After calculations, the RLC processing unit 6092 inputs the calculatedRLC layer throughputs to the external input/output unit 610.

The signal generating unit 6093, for example, encodes and data-modulatesan uplink shared channel, a sounding reference signal, and/or an uplinkcontrol channel such as downlink quality information and acknowledgementinformation for a downlink shared channel, and thereby generates anuplink transmission signal.

The transmission processing unit 6094 performs transmission processingsuch as DFT processing, IFFT processing, and CP addition.

The external input/output unit 610 outputs calculated (measured) valuesfrom the uplink quality measuring unit 6086, the downlink qualitymeasuring unit 6087, the reference signal measuring unit 6089, the MACprocessing unit 6091, and the RLC processing unit 6092 of the basebandsignal processing unit 608, the call processing unit 612, and theapplication unit 614 to external interfaces. For example, the externalinput/output unit 610 displays the calculated values as numerical dataand/or graphs on a monitor screen or stores the calculated values asnumerical data in a storage medium such as a memory or a hard disk.

The external input/output unit 610 also receives information regarding aserving cell at a given timing from the call processing unit 612. Theexternal input/output unit 610 may output the calculated values to anexternal interface (e.g., a monitor screen or a storage medium) togetherwith the information regarding the serving cell.

Also, the external input/output unit 610 may obtain positionalinformation of the receiving apparatus 600 and output calculated(measured) values from the uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, and the reference signal measuringunit 6089 to an external interface (e.g., a monitor screen or a storagemedium) together with the positional information. The positionalinformation may be obtained, for example, from a positional informationobtaining device such as the GPS 700 connected to the externalinput/output unit 610.

When output together with the positional information, the calculated(measured) values from the uplink quality measuring unit 6086, thedownlink quality measuring unit 6087, the reference signal measuringunit 6089, the MAC processing unit 6091, the RLC processing unit 6092,and the application unit 614 may be represented by averages in the timedomain or averages calculated based on the positional information.

Also, when the calculated values are averaged based on the positionalinformation instead of in the time domain by the uplink qualitymeasuring unit 6086, the downlink quality measuring unit 6087, thereference signal measuring unit 6089, the MAC processing unit 6091, theRLC processing unit 6092, and the application unit 614, the positionalinformation obtained from the GPS 700 is input via the externalinput/output unit 610 to the corresponding units.

The external input/output unit 610 may also be configured to storeparameters used by the uplink quality measuring unit 6086, the downlinkquality measuring unit 6087, the reference signal measuring unit 6089,the MAC processing unit 6091, and the RLC processing unit 6092 of thebaseband signal processing unit 608 and the application unit 614, and toinput the parameters to the corresponding units. The parameters may bestored as internal parameters of the receiving apparatus 600 or may beinput from an external interface.

The call processing unit 612 performs call processing such asestablishment, handover, and release of communication channels, andstatus management of the receiving apparatus 600.

The call processing unit 612 also receives calculated (measured) valuesregarding a downlink reference signal transmitted from the serving cell,i.e., the base station 200, and a neighboring base station from thereference signal measuring unit 6089 of the baseband signal processingunit 608, generates a measurement report based on the downlink referencesignal, and transmits the measurement report via the baseband signalprocessing unit 608, the transceiver unit 606, the amplifier 604, andthe antenna 602 to the base station 200.

The call processing unit 612 also outputs the contents of themeasurement report to the external input/output unit 610. The contentsof the measurement report input to the external input/output unit 610are output, for example, as graphs or numerical data to the outside(e.g., a monitor screen or a storage medium) as described later. Also,contents of the measurement report may be output as graphs or numericaldata to the outside (e.g., a monitor screen or a storage medium)together with the positional information of the receiving apparatus 600.Thus, the contents of the measurement report are output to the outsideto allow a network operator (or a user, a device, or so on) to determinewhether the quality of handover is appropriately maintained and tooptimize parameters related to handover such as handover hysteresis and“time to trigger”.

Also, the call processing unit 612 reports, for example, information onthe current serving cell to the components of the baseband signalprocessing unit 608 and the external input/output unit 610.

The application unit 614 performs processing regarding upper layershigher than the physical layer, the MAC layer, and the RLC layer.

The application unit 614 uploads and downloads files to and from aserver to enable the receiving apparatus 600 to continue communicationswith the base station 200.

The application unit 614 may also be configured to measure uplink anddownlink TCP layer throughputs and to input the measured throughputs tothe external input/output unit 610.

The TCP layer throughputs may be represented by averages in the timedomain. An average in the time domain may be calculated over anaveraging period defined as a parameter. For example, an average may becalculated over an averaging period of 1 s. Also, the average calculatedover 1 s may be filtered using the following formula to obtain a valueF_(n):F _(n)=(1−a)×F _(n-1) +a×M _(n)

where,

F_(n): current value obtained by filtering

F_(n-1): previous value obtained by filtering

a: filtering factor

M_(n): average over 1 s

For example, the filtering factor “a” may be set at ½^((k/2)) (k=0, 1,2, . . . ). The averaging period and the filtering factor “a” may beprovided as parameters in the receiving apparatus 600 or may be inputfrom the outside via the external input/output unit 110.

Instead of averaging throughputs in the time domain as described above,throughputs may be averaged based on positional information of thereceiving apparatus 600. For example, TCP layer throughputs may beaveraged over an averaging interval of 100 m, i.e., every 100-m movementof the receiving apparatus 600. A two-dimensional parameter such as 100m² may be specified for the averaging interval instead of aone-dimensional parameter such as 100 m. The positional information isinput via the external input/output unit 610. The averaging intervalbased on the positional information may be provided as a parameter inthe receiving apparatus 600 or may be input from the outside via theexternal input/output unit 610.

Also, the application unit 614 may be configured to calculate a TCPlayer throughput based on resource allocation information in thefrequency domain and/or the time domain. That is, the application unit614 may calculate an actual TCP layer throughput or calculate a TCPlayer throughput based on an assumption that all frequency and timeresources are allocated to the receiving apparatus 600. Also, theapplication unit 614 may calculate a TCP layer throughput based onhypothetical frequency and time resources (allocation frequency) inputfrom the outside via the external input/output unit 610.

Further, the application unit 614 may be configured to obtain dump dataof the TCP layer and to obtain data regarding temporal change in the TCPsequence number, duplicate ACK, and TCP retransmission from the dumpdata.

The application unit 614 inputs the uplink and downlink TCP layerthroughputs and the obtained data regarding temporal change in the TCPsequence number, duplicate ACK, and TCP retransmission to the externalinput/output unit 610.

Fourth Embodiment

A receiving apparatus 600 for communication area evaluation according toa fourth embodiment of the present invention is different from thereceiving apparatuses of the above embodiments in that it includesmultiple receiving units having different receiving capabilities. Here,“receiving capability” is defined, for example, by the number ofreceiving antennas, a distance between multiple receiving antennas, adifference in antenna gain between multiple receiving antennas, areceiving algorithm, and/or a signal separation algorithm in MIMO.

The receiving apparatus 600 of this embodiment has a configurationsimilar to that shown in FIG. 5 or FIG. 18, but includes multiplebaseband signal processing units having different receivingcapabilities. Each of the baseband signal processing units, for example,includes an uplink quality measuring unit 6086, a downlink qualitymeasuring unit 6087, a delay profile measuring unit 6088, a referencesignal measuring unit 6089, and an error rate obtaining unit 6090; andcalculates and outputs uplink quality, downlink quality, a delayprofile, a reference signal measurement, and an error rate correspondingto its receiving capability. In other words, the baseband signalprocessing units output multiple sets of calculation results. Also inthis case, each of the baseband signal processing units may beconfigured to obtain positional information of the receiving apparatus600 and to output uplink quality, downlink quality, a delay profile, areference signal measurement, and an error rate in association with thepositional information.

A receiving apparatus including multiple baseband signal processingunits with different receiving capabilities makes it possible tosimultaneously evaluate communication qualities for different receivingcapabilities and thereby makes it possible to determine effectivedifferences between the receiving capabilities. Also, it is possible toprovide a highly-efficient communication system by designing a service(or communication) area based on such evaluation results.

In the above embodiments, it is assumed that the radio communicationsystem 1000 is based on Evolved UTRA and UTRAN (also called Long TermEvolution or Super 3G). However, a mobile station, a base station, amobile communication system, and a communication control methodaccording to aspects of the present invention may be used for any systemusing shared channels for communications. For example, the presentinvention may also be applied to W-CDMA and HSDPA in 3GPP and 1xEV-DOand UMB in 3GPP2.

Although specific values are used in the above descriptions tofacilitate the understanding of the present invention, the values arejust examples and different values may also be used unless otherwisementioned.

The present invention is not limited to the specifically disclosedembodiments, and variations and modifications may be made withoutdeparting from the scope of the present invention. Although functionalblock diagrams are used to describe apparatuses in the aboveembodiments, the apparatuses may be implemented by hardware, software,or a combination of them.

The present international application claims priority from JapanesePatent Application No. 2007-211590 filed on Aug. 14, 2007, the entirecontents of which are hereby incorporated herein by reference.

The invention claimed is:
 1. A receiving apparatus, comprising: aplurality of receiving units, each of which includes a plurality ofreceiving antennas and is configured to receive a first signaltransmitted from a base station, wherein the plurality of receivingunits have different receiving capabilities; a plurality of estimatedvalue calculation units each of which is configured to obtain downlinkquality information based on the first signal received by acorresponding one of the plurality of receiving units and to calculatean estimated downlink throughput corresponding to the receivingcapabilities based on the downlink quality information, wherein theplurality of receiving units comprises the plurality of estimated valuecalculation units; the plurality of receiving units are configured tocalculate uplink quality, a delay profile, and an error ratecorresponding to the receiving capabilities; and an outputting unitconfigured to output the plurality of the estimated downlink throughputscalculated by the estimated value calculation units, the uplink quality,the delay profile, and the error rate; and wherein the receivingcapabilities are defined by a number of receiving antennas, a distancebetween multiple receiving antennas, a difference in antenna gainbetween multiple receiving antennas, a receiving algorithm, and a signalseparation algorithm in MIMO.
 2. The receiving apparatus as claimed inclaim 1, wherein when the base station includes multiple transmittingantennas, the estimated value calculation unit is configured to obtainthe downlink quality information including a number of streams (rank) inMIMO.
 3. The receiving apparatus as claimed in claim 1, wherein thedownlink quality information and the estimated downlink throughput areradio quality information and a throughput of an entire frequency bandof a mobile communication system, or radio quality information and athroughput of a part of the entire frequency band of the mobilecommunication system.
 4. The receiving apparatus as claimed in claim 1,wherein the first signal is a downlink reference signal or a commonpilot channel.
 5. The receiving apparatus as claimed in claim 1, furthercomprising: a positional information obtaining unit configured to obtainpositional information of the receiving apparatus, wherein theoutputting unit is configured to output the estimated downlinkthroughput in association with the positional information.
 6. A dataobtaining method, comprising: a receiving step of receiving, from aplurality of receiving units each of which includes a plurality ofreceiving antennas, a first signal transmitted from a base station,wherein the plurality of receiving units have different receivingcapabilities; a quality information obtaining step of obtaining downlinkquality information based on the first signal; an estimated valuecalculation step of calculating, with a plurality of estimated valuecalculation units each of which is configured to obtain the downlinkquality information based on the first signal received by acorresponding one of the plurality of receiving units, an estimateddownlink throughput corresponding to the receiving capabilities based onthe downlink quality information, wherein the plurality of receivingunits comprises the plurality of estimated value calculation units; acalculating step of calculating, with the plurality of receiving units,uplink quality, delay profile, and an error rate corresponding to thereceiving capabilities: and an outputting step of outputting theplurality of the estimated downlink throughputs calculated by theestimated value calculation units, the uplink quality, the delayprofile, and the error rate; and wherein the receiving capabilities aredefined by a number of receiving antennas, a distance between multiplereceiving antennas, a difference in antenna gain between multiplereceiving antennas, a receiving algorithm, and a signal separationalgorithm in MIMO.
 7. A receiving apparatus, comprising: a plurality ofreceiving units, each of which includes a plurality of receivingantennas and is configured to receive a first signal transmitted frommultiple base stations that perform downlink transmission insynchronization with each other, wherein the plurality of receivingunits have different receiving capabilities; a plurality of estimatedvalue calculation units each of which is configured to obtain downlinkquality information based on the first signal received by acorresponding one of the plurality of receiving units and to calculatean estimated downlink throughput corresponding to the receivingcapabilities based on the downlink quality information, wherein theplurality of receiving units comprises the plurality of estimated valuecalculation units; the plurality of receiving units are configured tocalculate uplink quality, a delay profile, and an error ratecorresponding to the receiving capabilities; and an outputting unitconfigured to output the plurality of the estimated downlink throughputscalculated by the estimated value calculation units, the uplink quality,the delay profile and the error rate; and wherein the receivingcapabilities are defined by a number of receiving antennas, a distancebetween multiple receiving antennas, a difference in antenna gainbetween multiple receiving antennas, a receiving algorithm, and a signalseparation algorithm in MIMO.
 8. The receiving apparatus as claimed inclaim 7, wherein the first signal is a downlink reference signal or acommon pilot channel.
 9. The receiving apparatus as claimed in claim 7,further comprising: a positional information obtaining unit configuredto obtain positional information of the receiving apparatus, wherein theoutputting unit is configured to output the estimated downlinkthroughput in association with the positional information.
 10. A dataobtaining method, comprising: a receiving step of receiving, from aplurality of receiving, units each of which includes a plurality ofreceiving antennas, a first signal transmitted from multiple basestations that perform downlink transmission in synchronization with eachother, wherein the plurality of receiving units have different receivingcapabilities; a quality information obtaining step of obtaining downlinkquality information based on the first signal; an estimated valuecalculation step of calculating, with a plurality of estimated valuecalculation units each of which is configured to obtain the downlinkquality information based on the first signal received by acorresponding one of the plurality of receiving units, an estimateddownlink throughput corresponding to the receiving capabilities based onthe downlink quality information, wherein the plurality of receivingunits comprises the plurality of estimated value calculation units: acalculating step of calculating, with the plurality of receiving units,uplink quality, a delay profile, and an error rate corresponding to thereceiving capabilities; and an outputting step of outputting theplurality of the estimated downlink throughputs calculated by theestimated value calculation units, the uplink quality, the delayprofile, and the error rate; and wherein the receiving capabilities aredefined by a number of receiving antennas, a distance between multiplereceiving antennas, a difference in antenna gain between multiplereceiving antennas, a receiving algorithm, and a signal separationalgorithm in MIMO.